CA2165251A1 - Deinking composition and process - Google Patents
Deinking composition and processInfo
- Publication number
- CA2165251A1 CA2165251A1 CA 2165251 CA2165251A CA2165251A1 CA 2165251 A1 CA2165251 A1 CA 2165251A1 CA 2165251 CA2165251 CA 2165251 CA 2165251 A CA2165251 A CA 2165251A CA 2165251 A1 CA2165251 A1 CA 2165251A1
- Authority
- CA
- Canada
- Prior art keywords
- range
- per molecule
- groups per
- formula
- carbon number
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 239000002761 deinking Substances 0.000 title claims abstract description 76
- 238000000034 method Methods 0.000 title claims abstract description 68
- 239000000203 mixture Substances 0.000 title claims abstract description 15
- 230000008569 process Effects 0.000 title abstract description 24
- 108090000790 Enzymes Proteins 0.000 claims abstract description 56
- 102000004190 Enzymes Human genes 0.000 claims abstract description 56
- GOOHAUXETOMSMM-UHFFFAOYSA-N Propylene oxide Chemical compound CC1CO1 GOOHAUXETOMSMM-UHFFFAOYSA-N 0.000 claims abstract description 49
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 41
- 239000010893 paper waste Substances 0.000 claims abstract description 34
- DNIAPMSPPWPWGF-UHFFFAOYSA-N Propylene glycol Chemical compound CC(O)CO DNIAPMSPPWPWGF-UHFFFAOYSA-N 0.000 claims abstract description 30
- 238000005188 flotation Methods 0.000 claims abstract description 30
- 239000002736 nonionic surfactant Substances 0.000 claims abstract description 25
- 235000014113 dietary fatty acids Nutrition 0.000 claims abstract description 24
- 239000000194 fatty acid Substances 0.000 claims abstract description 24
- 229930195729 fatty acid Natural products 0.000 claims abstract description 24
- 150000004665 fatty acids Chemical class 0.000 claims abstract description 24
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 21
- -1 polyethylene Polymers 0.000 claims abstract description 18
- 239000012736 aqueous medium Substances 0.000 claims abstract description 17
- 238000005406 washing Methods 0.000 claims abstract description 16
- WVDDGKGOMKODPV-UHFFFAOYSA-N Benzyl alcohol Chemical compound OCC1=CC=CC=C1 WVDDGKGOMKODPV-UHFFFAOYSA-N 0.000 claims abstract description 10
- 229920005676 ethylene-propylene block copolymer Polymers 0.000 claims abstract description 10
- 229920005674 ethylene-propylene random copolymer Polymers 0.000 claims abstract description 10
- DNIAPMSPPWPWGF-GSVOUGTGSA-N (R)-(-)-Propylene glycol Chemical compound C[C@@H](O)CO DNIAPMSPPWPWGF-GSVOUGTGSA-N 0.000 claims abstract description 6
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 6
- 239000004698 Polyethylene Substances 0.000 claims abstract description 6
- 239000004743 Polypropylene Substances 0.000 claims abstract description 6
- 239000002253 acid Substances 0.000 claims abstract description 6
- 125000001931 aliphatic group Chemical group 0.000 claims abstract description 6
- 229920000573 polyethylene Polymers 0.000 claims abstract description 6
- 229920001155 polypropylene Polymers 0.000 claims abstract description 6
- 229940088598 enzyme Drugs 0.000 claims description 55
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 54
- 229910052799 carbon Inorganic materials 0.000 claims description 54
- 125000000217 alkyl group Chemical group 0.000 claims description 48
- 125000006353 oxyethylene group Chemical group 0.000 claims description 47
- 150000002191 fatty alcohols Chemical class 0.000 claims description 25
- IAYPIBMASNFSPL-UHFFFAOYSA-N Ethylene oxide Chemical compound C1CO1 IAYPIBMASNFSPL-UHFFFAOYSA-N 0.000 claims description 16
- 230000000694 effects Effects 0.000 claims description 14
- 108010059892 Cellulase Proteins 0.000 claims description 8
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical class OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims description 8
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 claims description 8
- 235000019256 formaldehyde Nutrition 0.000 claims description 8
- 125000000954 2-hydroxyethyl group Chemical group [H]C([*])([H])C([H])([H])O[H] 0.000 claims description 5
- 229940106157 cellulase Drugs 0.000 claims description 5
- 229920001223 polyethylene glycol Chemical class 0.000 claims description 5
- 239000002202 Polyethylene glycol Chemical class 0.000 claims description 4
- 150000002193 fatty amides Chemical class 0.000 claims description 4
- 150000002334 glycols Chemical class 0.000 claims description 4
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Chemical class OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 claims description 4
- 238000007865 diluting Methods 0.000 claims description 2
- 230000007935 neutral effect Effects 0.000 abstract description 7
- 239000002609 medium Substances 0.000 abstract description 5
- 239000000976 ink Substances 0.000 description 36
- 239000000543 intermediate Substances 0.000 description 32
- 239000000123 paper Substances 0.000 description 16
- 239000000835 fiber Substances 0.000 description 15
- 239000000126 substance Substances 0.000 description 15
- 239000004094 surface-active agent Substances 0.000 description 14
- 239000013055 pulp slurry Substances 0.000 description 13
- 238000002474 experimental method Methods 0.000 description 11
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- 239000002002 slurry Substances 0.000 description 9
- 238000005259 measurement Methods 0.000 description 8
- 238000004537 pulping Methods 0.000 description 8
- 238000012360 testing method Methods 0.000 description 7
- 239000002699 waste material Substances 0.000 description 6
- 238000002156 mixing Methods 0.000 description 5
- 238000005070 sampling Methods 0.000 description 5
- 108010084185 Cellulases Proteins 0.000 description 4
- 102000005575 Cellulases Human genes 0.000 description 4
- 230000002378 acidificating effect Effects 0.000 description 4
- 230000004913 activation Effects 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 102000002568 Multienzyme Complexes Human genes 0.000 description 3
- 108010093369 Multienzyme Complexes Proteins 0.000 description 3
- 241000282320 Panthera leo Species 0.000 description 3
- 238000013019 agitation Methods 0.000 description 3
- 150000001298 alcohols Chemical class 0.000 description 3
- 238000003556 assay Methods 0.000 description 3
- 239000011230 binding agent Substances 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 239000003921 oil Substances 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 230000002829 reductive effect Effects 0.000 description 3
- 241000233866 Fungi Species 0.000 description 2
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 2
- 238000005054 agglomeration Methods 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- FYGDTMLNYKFZSV-CSHPIKHBSA-N beta-cellotriose Chemical compound O[C@@H]1[C@@H](O)[C@H](O)[C@@H](CO)O[C@H]1O[C@@H]1[C@@H](CO)O[C@@H](O[C@@H]2[C@H](O[C@@H](O)[C@H](O)[C@H]2O)CO)[C@H](O)[C@H]1O FYGDTMLNYKFZSV-CSHPIKHBSA-N 0.000 description 2
- 239000000872 buffer Substances 0.000 description 2
- 239000001913 cellulose Substances 0.000 description 2
- 229920002678 cellulose Polymers 0.000 description 2
- 238000010191 image analysis Methods 0.000 description 2
- 239000011087 paperboard Substances 0.000 description 2
- 150000002978 peroxides Chemical class 0.000 description 2
- 238000011020 pilot scale process Methods 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 239000003760 tallow Substances 0.000 description 2
- 239000008399 tap water Substances 0.000 description 2
- 235000020679 tap water Nutrition 0.000 description 2
- 238000010998 test method Methods 0.000 description 2
- NYYSPVRERVXMLJ-UHFFFAOYSA-N 4,4-difluorocyclohexan-1-one Chemical compound FC1(F)CCC(=O)CC1 NYYSPVRERVXMLJ-UHFFFAOYSA-N 0.000 description 1
- 241000228245 Aspergillus niger Species 0.000 description 1
- 238000012935 Averaging Methods 0.000 description 1
- 241000193830 Bacillus <bacterium> Species 0.000 description 1
- 241000894006 Bacteria Species 0.000 description 1
- 229920003043 Cellulose fiber Polymers 0.000 description 1
- KRKNYBCHXYNGOX-UHFFFAOYSA-K Citrate Chemical compound [O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O KRKNYBCHXYNGOX-UHFFFAOYSA-K 0.000 description 1
- 235000013162 Cocos nucifera Nutrition 0.000 description 1
- 244000060011 Cocos nucifera Species 0.000 description 1
- 241000196324 Embryophyta Species 0.000 description 1
- 101710166469 Endoglucanase Proteins 0.000 description 1
- 241000223198 Humicola Species 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 241001465754 Metazoa Species 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
- RVGRUAULSDPKGF-UHFFFAOYSA-N Poloxamer Chemical compound C1CO1.CC1CO1 RVGRUAULSDPKGF-UHFFFAOYSA-N 0.000 description 1
- 239000005062 Polybutadiene Substances 0.000 description 1
- 239000004793 Polystyrene Substances 0.000 description 1
- 239000004115 Sodium Silicate Substances 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 1
- 241000223259 Trichoderma Species 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 239000002518 antifoaming agent Substances 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 239000007900 aqueous suspension Substances 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000003139 buffering effect Effects 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- 239000004359 castor oil Substances 0.000 description 1
- 235000019438 castor oil Nutrition 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000002738 chelating agent Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 230000009849 deactivation Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- QFYBYZLHPIALCZ-ZETCQYMHSA-N eglu Chemical compound CC[C@@](N)(C(O)=O)CCC(O)=O QFYBYZLHPIALCZ-ZETCQYMHSA-N 0.000 description 1
- 125000000816 ethylene group Chemical group [H]C([H])([*:1])C([H])([H])[*:2] 0.000 description 1
- 238000000855 fermentation Methods 0.000 description 1
- 230000004151 fermentation Effects 0.000 description 1
- 239000002657 fibrous material Substances 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- ZEMPKEQAKRGZGQ-XOQCFJPHSA-N glycerol triricinoleate Natural products CCCCCC[C@@H](O)CC=CCCCCCCCC(=O)OC[C@@H](COC(=O)CCCCCCCC=CC[C@@H](O)CCCCCC)OC(=O)CCCCCCCC=CC[C@H](O)CCCCCC ZEMPKEQAKRGZGQ-XOQCFJPHSA-N 0.000 description 1
- 108010002430 hemicellulase Proteins 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 238000010348 incorporation Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 239000003562 lightweight material Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000002803 maceration Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000009896 oxidative bleaching Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 230000001717 pathogenic effect Effects 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 229960000502 poloxamer Drugs 0.000 description 1
- 229920001983 poloxamer Polymers 0.000 description 1
- 229920002857 polybutadiene Polymers 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 150000003138 primary alcohols Chemical class 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000009895 reductive bleaching Methods 0.000 description 1
- 238000007127 saponification reaction Methods 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- JVBXVOWTABLYPX-UHFFFAOYSA-L sodium dithionite Chemical compound [Na+].[Na+].[O-]S(=O)S([O-])=O JVBXVOWTABLYPX-UHFFFAOYSA-L 0.000 description 1
- 239000001488 sodium phosphate Substances 0.000 description 1
- 229910000162 sodium phosphate Inorganic materials 0.000 description 1
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000007655 standard test method Methods 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 235000011149 sulphuric acid Nutrition 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- RYFMWSXOAZQYPI-UHFFFAOYSA-K trisodium phosphate Chemical compound [Na+].[Na+].[Na+].[O-]P([O-])([O-])=O RYFMWSXOAZQYPI-UHFFFAOYSA-K 0.000 description 1
- 238000004383 yellowing Methods 0.000 description 1
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C5/00—Other processes for obtaining cellulose, e.g. cooking cotton linters ; Processes characterised by the choice of cellulose-containing starting materials
- D21C5/005—Treatment of cellulose-containing material with microorganisms or enzymes
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C5/00—Other processes for obtaining cellulose, e.g. cooking cotton linters ; Processes characterised by the choice of cellulose-containing starting materials
- D21C5/02—Working-up waste paper
- D21C5/025—De-inking
- D21C5/027—Chemicals therefor
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/64—Paper recycling
Abstract
This invention relates to the deinking process for office wastepaper for utilization in a neutral medium. Particularly the invention relates to a deinking process for office wastepaper comprising the steps of: (a) converting wastepaper to pulp; (b) contacting the pulp with a deinking agent comprising of: i) an enzyme active at a pH of from about 4 to about 9 and ii) a nonionic surfactant selected from the group consisting of higher aliphatic alcohol alkoxylates, aliphatic acid alkoxylates, higher aromatic alcohol alkoxylates, fatty acid amides of alkanolamines, fatty acid amide alkoxylates, propylene glycol alkoxylates, block or random copolymers of ethylene and propylene oxide, higher alcohol polyethylene polypropylene block or random adducts and mixtures thereof; in an aqueous medium having a pH of from about 4 to about 9; and (c) removing ink from the pulp by flotation, water washing or a combination of flotation and water washing.
Description
` 2165251 DEINKING COMPOSITION AND PROCESS
Technical Field This invention relates generally to the deinking of office wastepaper. In particular, the invention relates to a deinking process for office wastepaper suitable for utilization in a neutral medium.
Background of the Invention Wastepaper has long served as a source of raw fiber material for paperm~king. Ithas been standard practice in the art to reclaim wastepaper to allow the reclaimed paper fibers to be used as part or all of the stock of subsequent production of a variety of paper and paperboard products. Today, greater utilization of reclaimed fiber has provided incentive for taking steps to upgrade the reclaimed product.
These steps include treatment to effectively remove ink from waste fibers in order to permit their use in the m~nuf~cture of newsprint and high quality papers.
Increasing amounts of office wastepaper are becoming available with the increased participation by businesses in recycling. Because of the high quality cellulose fiber in office wastepaper, efficient ink removal is particularly desirable since excellent quality, high value products such as office stationery can be prepared.
In the course of conventional paper reclamation, deinking procedures include steps for converting the wastepaper to pulp and contacting the pulp with an alkaline aqueous deinking medium cont~ining a chemical deinking agent. The physical pulping and the alkalinity of the aqueous medium cause the partial removal of ink from the pulp fiber. The deinking agent completes this removal and produces an aqueous suspension and/or dispersion of the ink particles. The resulting mixture is subsequently treated to separate the suspended/dispersed ink from the pulp. Thisseparation may be by flotation and/ or washing techniques known in the art.
216525~
Conventional deinking chemicals comprise a complex mixture of chemicals, e.g., sodium hydroxide, sodium silicate, chelating agents, hydrogen peroxide, surfactants, dispersants, collector chemicals and agglomeration chemicals.
Generally, including a significant amount of alkaline material is standard in the art.
It is believed that the alkaline material is needed for good saponification and hydrolysis of the ink resins as well as enhancement of fiber flexibility. The pH of the pulp during the deinking process is usually from about 9.5 to about 11.
Exposing the cellulosic fibers to this degree of alkalinity tends to cause yellowing of the fibers; so, it is generally necessary to add an oxidative or reductive bleaching o agent such as peroxide, formamidine sulfinic acid or sodium hydrosulfite. The use of this complex and highly alkaline mixture of chemicals is undesirable since the liquor that results from the deinking process presents significant environmentaldisposal problems.
There is a need for a method of deinking that operates under slightly acidic to slightly alkaline or preferably neutral pH conditions and utilizes a simple combination of chemicals. Such a method could result in waste liquors with significantly reduced disposal problems. Conventional processes have not been particularly successful in specific application to xerographically printed and laser printed paper found in office wastepaper. The difficulty encountered in the deinking of these fused toner papers (laser and Xerox produced) has been attributed to the character of the electrostatic ink, specifically to the binder, which is fundamentally different from that used in other printing processes. For example, in distinction to the common oil or resin binders of other inks, the electrostatic ink binder is typically a polymeric material, e.g., polystyrene and polybutadiene, which during the printing process is fixed to the paper by application of pressure and heat.
It is the ink-fusing action of the copier or laser printer that upon repulping results in large, plate-like structures which are typically too large to be removed by washing or flotation and too flat to be removed by screens and cleaners. The approach that several chemical companies have taken is to chemically modify the surface of the toner flakes such that agglomeration will occur. The substantially larger particles will then be removed by slotted pressure screens and forward centrifugal cleaners.
U.S. Patent Nos. 5,231,022 and 5,318,905 teach the use of highly alkaline cellulase s enzymes for use in the deinking of waste newspaper. The enzyme optimally operates at a pH of about 9.5 to about 10.5.
Japan Published Application No. 59-9299 teaches a method for deinking waste newspaper and m~g~7ine print. The method involves the combined use of a o surfactant with an enzym . Cellulase enzymes are suggested for use, particularly those which operate effectively under basic pH conditions (i.e., pH of 8.0 to 11.5).
The reference does not disclose nor suggest that its teachings can be utilized for deinking mixed office waste, which utilizes inks and print processing conditionsthat far differ from those used in newsprint and m~g~7ine print.
Despite the above teachings, there exists a clear need in the art for a method which effectively functions to deink mixed office waste and is operative at slightly acidic to slightly neutral pH aqueous environments.
Brief Summary of the Invention Surprisingly a deinking agent has been discovered which is suitable for use in amedium having a pH of from slightly acidic (about 4) to slightly alkaline (about 9), or preferably neutral medium. The deinking agent is effective in the treatment of office wastepaper by providing reclaimed pulp fiber having a high degree of dirtremoval and good brightness. A process for deinking office wastepaper utili7ing the deinking agent has been discovered which provides excellent ink and dirt removal as well as good brightness. The deinking agent can also be utilized in aconventional flotation deinking system and/or washing deinking system with little or no modification. Further, a complex mixture of chemicals is unnecessary when lltili~ing the deinking process and deinking agent of the present invention.
216~2Sl The present invention relates to a deinking process for office wastepaper comprising the steps of:
a) converting wastepaper to pulp;
b) contacting the pulp with a deinking agent comprising:
i) an enzyme active at a pH of from about 4 to about 9; and ii) a nonionic surfactant selected from the group consisting of higher aliphatic alcohol alkoxylates, aliphatic acid alkoxylates, higher aromatic alcohol alkoxylates, fatty acid amides of alkanolamines, fatty acid amide alkoxylates, o propylene glycol alkoxylates, block or random copolymers of ethylene and propylene oxide, higher alcohol polyethylene polypropylene block or random adducts and mixtures thereof;
in an aqueous medium having a pH of from about 4 to about 9; and c) removing ink from the pulp by flotation, water washing or a combination of flotation and water washing.
It is an object of the present invention to provide a process for deinking office wastepaper.
It is an additional object of the present invention to provide a novel deinking agent.
These and other objects will be appreciated by those skilled in the art as reference is made to the Drawings and Detailed Description of the Preferred Embodiment.
Brief Description of the Drawin~s Figure 1 is a diagram of the method used in Example XI.
Figures 2 and 3 are comparison graphs of results obtained when using InkmasterTM750 alone versus a combination of InkmasterTM 750 and SP342 as the res~ective deinking agents.
Detailed Description of the Preferred Embodiment In describing the preferred embodiment, certain terminology will be utilized for the sake of clarity. Such terminology is intended to encompass the recited embodiment, as well as all technical equivalents which operate in a similar manner for a similar purpose to achieve a similar result.
(a) Definitions:
o "Alkyl" means a carbon-cont:~ining chain which can be straight, branched or cyclic; substituted (mono- or poly-) or unsubstituted; and saturated or unsaturated.
"Enzyme" comprises multi-enzyme complexes and mixtures of enzymes.
"Fatty alcohol(s)" comprises primary, secondary and tertiary, straight-chain or branched alcohols, preferably primary, straight-chain alcohols having between about 8 and about 30 carbon atoms. Alcohols suitable for use include coconut fatty alcohols, tallow fatty alcohols, animal tallow fatty alcohols and mixtures thereof.
Also, stearyl fatty alcohols, oleyl fatty alcohols, palmityl fatty alcohols and arachidyl fatty alcohols can be used individually or in blends. They can be prepared synthetically or can be derived from natural oils. Preferred for use are straight-chain primary alcohols with from about C8 to about C22 alkyl groups.
"Office wastepaper" means used papers comprising xerographically printed and laser printed paper preferably comprising a majority (generally greater than about 70%) and more preferably comprising all xerographically printed or laser printedpaper.
All percentages and ratios given are on a weight basis unless otherwise indicated.
(b) The Invention:
2165~5~
-The deinking agent for use in the deinking method of the present invention comprises an enzyme having activity, preferably optimal activity, at a pH range of from slightly acidic (about 4) to slightly alkaline (about 9) and a nonionic surfactant.
s An enzyme suitable for use is active (in an aqueous medium) at a pH of generallyfrom about 4 to about 9, preferably from about 4 to about 8, more preferably from about 5.5 to about 7.5, even more preferably from about 6 to about 7 and most preferably from about 6.5 to about 7. The enzyme is characterized by its ability to 0 modify and/or breakdown cellulosic or cellulose-bonded matter.
Examples of suitable enzymes include cellulase derived from ~nim~l~, plants, bacteria and fungi such as those produced by the fungi, Aspergillus niger, Trichoderma virde and Thielatia terrestris. Humicola and Bacillus. Preferred enzymes for use are cellulase enzymes. Multi-enzyme complexes that are substantially cellulases are also preferred.
Commercially marketed products preferred for use include:
a) DENIMAXTM (CAS Number and name: 9012-54-8, cellulase), produced by NOVO NORDISK BIOINDUSTRIALS, INC., which is a stabilized liquid endo-glllc~n~e obtained by submerged fermentation of a non-pathogenic mold having an activity of about 100 EGLU/ml (approximately 80 cmu/g as determined by Novo Assay method, AF275) and a pH range of from about 3.8 to about 8 and an optimal pH of from about 6 to about 8; and b) SP342TM, (CAS number and name: 9012-54-8, cellulase), produced by NOVO NORDISK BIOINDUSTRIALS, INC., which is a multi-enzyme complex, a mixture of cellulases and hemicellulases where cellulases comprise the majority of the catalytic activity. The complex is active within a pH range of from about 3.8 to about 8.
PreferTed enzymes for use have little or no endocellulase activity (less than ors equal to about O.Ol~g/g) as measured by Avicellase assay. This assay is standard in the art and is a measure of activity towards an insoluble cellulose substrate, where the activity is an expression of the amount of cellulose solubilzing power.
The limit of detection is approximately about 0.001 ~g/g.
o Nonionic surfactants suitable for use are higher (greater than C8) aliphatic alcohol alkoxylates, aliphatic acid alkoxylates, higher aromatic alcohol alkoxylates, fatty acid amides of alkanolamines, fatty acid amide alkoxylates, propylene glycol alkoxylates, block or random copolymers of ethylene and propylene oxide, higher (greater than C8) alcohol polyethylene polypropylene block or random adducts andmixtures thereof.
PreferTed nonionic surfactants are selected from the group consisting of:
l) a fatty alcchol having a carbon number of from about 8 to about 22, alkoxylated with ethylene oxide and propylene oxide, as represented by formula (I) R-O-(CH2CH2O)X-(CH2CH(CH3)-O)y-H (I);
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to 22; x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25; and y represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 10.
Examples of commercially available products are sold under the InkMasterTM and Antarox~ trademarks by Rhône-Poulenc Inc.;
2165~1 2) a fatty alcohol having a carbon number of from about 8 to about 22, alkoxylated with ethylene oxide and propylene oxide, as represented by formula (II):
R-O-(CH2CH20)x-(CH2CH(CH3)-O)y~(CH2CH20)x~~(CH2CH(CH3)~0)y~~H (II);
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22; x and x', which may be the same or different, represents the number of oxyethylene groups 0 per molecule and is in the range of from about 2 to about 25; and y and y', which may be the same or different represents the number of oxypropylene groups per molecule and is in the range of from 0 to about 10 Examples of commercially available products are sold under the InkMaster trademark by Rhône-Poulenc Inc.;
Technical Field This invention relates generally to the deinking of office wastepaper. In particular, the invention relates to a deinking process for office wastepaper suitable for utilization in a neutral medium.
Background of the Invention Wastepaper has long served as a source of raw fiber material for paperm~king. Ithas been standard practice in the art to reclaim wastepaper to allow the reclaimed paper fibers to be used as part or all of the stock of subsequent production of a variety of paper and paperboard products. Today, greater utilization of reclaimed fiber has provided incentive for taking steps to upgrade the reclaimed product.
These steps include treatment to effectively remove ink from waste fibers in order to permit their use in the m~nuf~cture of newsprint and high quality papers.
Increasing amounts of office wastepaper are becoming available with the increased participation by businesses in recycling. Because of the high quality cellulose fiber in office wastepaper, efficient ink removal is particularly desirable since excellent quality, high value products such as office stationery can be prepared.
In the course of conventional paper reclamation, deinking procedures include steps for converting the wastepaper to pulp and contacting the pulp with an alkaline aqueous deinking medium cont~ining a chemical deinking agent. The physical pulping and the alkalinity of the aqueous medium cause the partial removal of ink from the pulp fiber. The deinking agent completes this removal and produces an aqueous suspension and/or dispersion of the ink particles. The resulting mixture is subsequently treated to separate the suspended/dispersed ink from the pulp. Thisseparation may be by flotation and/ or washing techniques known in the art.
216525~
Conventional deinking chemicals comprise a complex mixture of chemicals, e.g., sodium hydroxide, sodium silicate, chelating agents, hydrogen peroxide, surfactants, dispersants, collector chemicals and agglomeration chemicals.
Generally, including a significant amount of alkaline material is standard in the art.
It is believed that the alkaline material is needed for good saponification and hydrolysis of the ink resins as well as enhancement of fiber flexibility. The pH of the pulp during the deinking process is usually from about 9.5 to about 11.
Exposing the cellulosic fibers to this degree of alkalinity tends to cause yellowing of the fibers; so, it is generally necessary to add an oxidative or reductive bleaching o agent such as peroxide, formamidine sulfinic acid or sodium hydrosulfite. The use of this complex and highly alkaline mixture of chemicals is undesirable since the liquor that results from the deinking process presents significant environmentaldisposal problems.
There is a need for a method of deinking that operates under slightly acidic to slightly alkaline or preferably neutral pH conditions and utilizes a simple combination of chemicals. Such a method could result in waste liquors with significantly reduced disposal problems. Conventional processes have not been particularly successful in specific application to xerographically printed and laser printed paper found in office wastepaper. The difficulty encountered in the deinking of these fused toner papers (laser and Xerox produced) has been attributed to the character of the electrostatic ink, specifically to the binder, which is fundamentally different from that used in other printing processes. For example, in distinction to the common oil or resin binders of other inks, the electrostatic ink binder is typically a polymeric material, e.g., polystyrene and polybutadiene, which during the printing process is fixed to the paper by application of pressure and heat.
It is the ink-fusing action of the copier or laser printer that upon repulping results in large, plate-like structures which are typically too large to be removed by washing or flotation and too flat to be removed by screens and cleaners. The approach that several chemical companies have taken is to chemically modify the surface of the toner flakes such that agglomeration will occur. The substantially larger particles will then be removed by slotted pressure screens and forward centrifugal cleaners.
U.S. Patent Nos. 5,231,022 and 5,318,905 teach the use of highly alkaline cellulase s enzymes for use in the deinking of waste newspaper. The enzyme optimally operates at a pH of about 9.5 to about 10.5.
Japan Published Application No. 59-9299 teaches a method for deinking waste newspaper and m~g~7ine print. The method involves the combined use of a o surfactant with an enzym . Cellulase enzymes are suggested for use, particularly those which operate effectively under basic pH conditions (i.e., pH of 8.0 to 11.5).
The reference does not disclose nor suggest that its teachings can be utilized for deinking mixed office waste, which utilizes inks and print processing conditionsthat far differ from those used in newsprint and m~g~7ine print.
Despite the above teachings, there exists a clear need in the art for a method which effectively functions to deink mixed office waste and is operative at slightly acidic to slightly neutral pH aqueous environments.
Brief Summary of the Invention Surprisingly a deinking agent has been discovered which is suitable for use in amedium having a pH of from slightly acidic (about 4) to slightly alkaline (about 9), or preferably neutral medium. The deinking agent is effective in the treatment of office wastepaper by providing reclaimed pulp fiber having a high degree of dirtremoval and good brightness. A process for deinking office wastepaper utili7ing the deinking agent has been discovered which provides excellent ink and dirt removal as well as good brightness. The deinking agent can also be utilized in aconventional flotation deinking system and/or washing deinking system with little or no modification. Further, a complex mixture of chemicals is unnecessary when lltili~ing the deinking process and deinking agent of the present invention.
216~2Sl The present invention relates to a deinking process for office wastepaper comprising the steps of:
a) converting wastepaper to pulp;
b) contacting the pulp with a deinking agent comprising:
i) an enzyme active at a pH of from about 4 to about 9; and ii) a nonionic surfactant selected from the group consisting of higher aliphatic alcohol alkoxylates, aliphatic acid alkoxylates, higher aromatic alcohol alkoxylates, fatty acid amides of alkanolamines, fatty acid amide alkoxylates, o propylene glycol alkoxylates, block or random copolymers of ethylene and propylene oxide, higher alcohol polyethylene polypropylene block or random adducts and mixtures thereof;
in an aqueous medium having a pH of from about 4 to about 9; and c) removing ink from the pulp by flotation, water washing or a combination of flotation and water washing.
It is an object of the present invention to provide a process for deinking office wastepaper.
It is an additional object of the present invention to provide a novel deinking agent.
These and other objects will be appreciated by those skilled in the art as reference is made to the Drawings and Detailed Description of the Preferred Embodiment.
Brief Description of the Drawin~s Figure 1 is a diagram of the method used in Example XI.
Figures 2 and 3 are comparison graphs of results obtained when using InkmasterTM750 alone versus a combination of InkmasterTM 750 and SP342 as the res~ective deinking agents.
Detailed Description of the Preferred Embodiment In describing the preferred embodiment, certain terminology will be utilized for the sake of clarity. Such terminology is intended to encompass the recited embodiment, as well as all technical equivalents which operate in a similar manner for a similar purpose to achieve a similar result.
(a) Definitions:
o "Alkyl" means a carbon-cont:~ining chain which can be straight, branched or cyclic; substituted (mono- or poly-) or unsubstituted; and saturated or unsaturated.
"Enzyme" comprises multi-enzyme complexes and mixtures of enzymes.
"Fatty alcohol(s)" comprises primary, secondary and tertiary, straight-chain or branched alcohols, preferably primary, straight-chain alcohols having between about 8 and about 30 carbon atoms. Alcohols suitable for use include coconut fatty alcohols, tallow fatty alcohols, animal tallow fatty alcohols and mixtures thereof.
Also, stearyl fatty alcohols, oleyl fatty alcohols, palmityl fatty alcohols and arachidyl fatty alcohols can be used individually or in blends. They can be prepared synthetically or can be derived from natural oils. Preferred for use are straight-chain primary alcohols with from about C8 to about C22 alkyl groups.
"Office wastepaper" means used papers comprising xerographically printed and laser printed paper preferably comprising a majority (generally greater than about 70%) and more preferably comprising all xerographically printed or laser printedpaper.
All percentages and ratios given are on a weight basis unless otherwise indicated.
(b) The Invention:
2165~5~
-The deinking agent for use in the deinking method of the present invention comprises an enzyme having activity, preferably optimal activity, at a pH range of from slightly acidic (about 4) to slightly alkaline (about 9) and a nonionic surfactant.
s An enzyme suitable for use is active (in an aqueous medium) at a pH of generallyfrom about 4 to about 9, preferably from about 4 to about 8, more preferably from about 5.5 to about 7.5, even more preferably from about 6 to about 7 and most preferably from about 6.5 to about 7. The enzyme is characterized by its ability to 0 modify and/or breakdown cellulosic or cellulose-bonded matter.
Examples of suitable enzymes include cellulase derived from ~nim~l~, plants, bacteria and fungi such as those produced by the fungi, Aspergillus niger, Trichoderma virde and Thielatia terrestris. Humicola and Bacillus. Preferred enzymes for use are cellulase enzymes. Multi-enzyme complexes that are substantially cellulases are also preferred.
Commercially marketed products preferred for use include:
a) DENIMAXTM (CAS Number and name: 9012-54-8, cellulase), produced by NOVO NORDISK BIOINDUSTRIALS, INC., which is a stabilized liquid endo-glllc~n~e obtained by submerged fermentation of a non-pathogenic mold having an activity of about 100 EGLU/ml (approximately 80 cmu/g as determined by Novo Assay method, AF275) and a pH range of from about 3.8 to about 8 and an optimal pH of from about 6 to about 8; and b) SP342TM, (CAS number and name: 9012-54-8, cellulase), produced by NOVO NORDISK BIOINDUSTRIALS, INC., which is a multi-enzyme complex, a mixture of cellulases and hemicellulases where cellulases comprise the majority of the catalytic activity. The complex is active within a pH range of from about 3.8 to about 8.
PreferTed enzymes for use have little or no endocellulase activity (less than ors equal to about O.Ol~g/g) as measured by Avicellase assay. This assay is standard in the art and is a measure of activity towards an insoluble cellulose substrate, where the activity is an expression of the amount of cellulose solubilzing power.
The limit of detection is approximately about 0.001 ~g/g.
o Nonionic surfactants suitable for use are higher (greater than C8) aliphatic alcohol alkoxylates, aliphatic acid alkoxylates, higher aromatic alcohol alkoxylates, fatty acid amides of alkanolamines, fatty acid amide alkoxylates, propylene glycol alkoxylates, block or random copolymers of ethylene and propylene oxide, higher (greater than C8) alcohol polyethylene polypropylene block or random adducts andmixtures thereof.
PreferTed nonionic surfactants are selected from the group consisting of:
l) a fatty alcchol having a carbon number of from about 8 to about 22, alkoxylated with ethylene oxide and propylene oxide, as represented by formula (I) R-O-(CH2CH2O)X-(CH2CH(CH3)-O)y-H (I);
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to 22; x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25; and y represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 10.
Examples of commercially available products are sold under the InkMasterTM and Antarox~ trademarks by Rhône-Poulenc Inc.;
2165~1 2) a fatty alcohol having a carbon number of from about 8 to about 22, alkoxylated with ethylene oxide and propylene oxide, as represented by formula (II):
R-O-(CH2CH20)x-(CH2CH(CH3)-O)y~(CH2CH20)x~~(CH2CH(CH3)~0)y~~H (II);
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22; x and x', which may be the same or different, represents the number of oxyethylene groups 0 per molecule and is in the range of from about 2 to about 25; and y and y', which may be the same or different represents the number of oxypropylene groups per molecule and is in the range of from 0 to about 10 Examples of commercially available products are sold under the InkMaster trademark by Rhône-Poulenc Inc.;
3) a fatty acid having a carbon number of from about 8 to about 22, alkoxylated with ethylene oxide and propylene oxide, as represented by formula (III):
R-C(O)O-(CH2CH2O)X-(CH2CH(CH3)-O)y-H (III);
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22; x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25; and y represents the number of oxypropylene groups per molecule and is in the range of from about 2 to about 15.
Examples of commercially available products are Lionsurf3, Nonatell3, Hipochem3, and Berocell3 products sold respectively by Lion Industries, Inc., Shell Oil Company, High Point Chemical Corp. and EKA Nobel AB;
R-C(O)O-(CH2CH2O)X-(CH2CH(CH3)-O)y-H (III);
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22; x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25; and y represents the number of oxypropylene groups per molecule and is in the range of from about 2 to about 15.
Examples of commercially available products are Lionsurf3, Nonatell3, Hipochem3, and Berocell3 products sold respectively by Lion Industries, Inc., Shell Oil Company, High Point Chemical Corp. and EKA Nobel AB;
4) an aromatic alcohol such as phenol having alkyl chain(s) with a carbon number of from about 8 to about 20, alkoxylated with ethylene oxide, as represented by formula (IV):
21652~1 R~CH2CH2)X-OH (IV);
R' wherein R and R' independently are H or an alkyl group which is s branched or straight-chain having a carbon number of from about 8 to about 20; and x is the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20. Examples of commercially available products are InkMasterTM, Igepal~, and Alkasurf~, products sold by Rhône-Poulenc Inc.;
o 5) fatty amide of alkanolamide of formula (V):
R-C(O)-N-R' (V);
~"
wherein R' and R" may be the same or different and are H or 1S CH2CH2OH or CH2CH(CH3)-OH and R is a fatty alkyl group having a carbon number of from about 8 to about 20. Examples of commercially available products are Alkamide~ products sold by Rhône-Poulenc Inc.;
21652~1 R~CH2CH2)X-OH (IV);
R' wherein R and R' independently are H or an alkyl group which is s branched or straight-chain having a carbon number of from about 8 to about 20; and x is the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20. Examples of commercially available products are InkMasterTM, Igepal~, and Alkasurf~, products sold by Rhône-Poulenc Inc.;
o 5) fatty amide of alkanolamide of formula (V):
R-C(O)-N-R' (V);
~"
wherein R' and R" may be the same or different and are H or 1S CH2CH2OH or CH2CH(CH3)-OH and R is a fatty alkyl group having a carbon number of from about 8 to about 20. Examples of commercially available products are Alkamide~ products sold by Rhône-Poulenc Inc.;
6) an alkoxylated fatty acid amide of alkanolamide of formula (VI):
R- C(O)-N~CH2CH20),~-H
(CH2CH2O)~-H (VI) wherein R is a fatty alkyl group having a carbon number of from about 8 to about 20; and x represents the number of oxyethylene 2s groups per molecule and is in the range of from about 2 to about l O.
Examples of commercially available products are Alkamide~
products sold by Rhône-Poulenc Inc.;
R- C(O)-N~CH2CH20),~-H
(CH2CH2O)~-H (VI) wherein R is a fatty alkyl group having a carbon number of from about 8 to about 20; and x represents the number of oxyethylene 2s groups per molecule and is in the range of from about 2 to about l O.
Examples of commercially available products are Alkamide~
products sold by Rhône-Poulenc Inc.;
7) a propylene glycol alkoxylate of formula (VII):
HO-(CH2(~H20)o (CH2CH(CH3)-O)m (CH2CH20)p-H (VII) wherein o and p are the number of oxyethylene groups per molecule and are in the range of from about 3 to about 15 and m is the number of oxypropylene groups per molecule and is in the range of from about 25 to about 40 Examples of commercially available products are Antarox~ products sold by Rhône-Poulenc Inc. and products having a CTFA designation of Poloxamer;
HO-(CH2(~H20)o (CH2CH(CH3)-O)m (CH2CH20)p-H (VII) wherein o and p are the number of oxyethylene groups per molecule and are in the range of from about 3 to about 15 and m is the number of oxypropylene groups per molecule and is in the range of from about 25 to about 40 Examples of commercially available products are Antarox~ products sold by Rhône-Poulenc Inc. and products having a CTFA designation of Poloxamer;
8) a block or random copolymer of ethylene and propylene oxide of formula (VIII):
HO (CH(CH3)CH2O)m (CH2CH2O)p (CH(CH3)CH2O)nH (VIII) wherein m and n are the nurnber of oxypropylene groups per o molecule and are in the range of from about 10 to about 25 and p is the nurnber of oxyethylene groups per molecule and is in the range of from about 5 to about 25. Examples of commercially available products are Antarox~ products sold by Rhône-Poulenc Inc. and products having a CTFA designation of Meroxopol;
HO (CH(CH3)CH2O)m (CH2CH2O)p (CH(CH3)CH2O)nH (VIII) wherein m and n are the nurnber of oxypropylene groups per o molecule and are in the range of from about 10 to about 25 and p is the nurnber of oxyethylene groups per molecule and is in the range of from about 5 to about 25. Examples of commercially available products are Antarox~ products sold by Rhône-Poulenc Inc. and products having a CTFA designation of Meroxopol;
9) an ethoxylated fatty acid glycol and/or polyethylene glycol esters of formula (IX):
R-C(O)O-(CH2CH2O)x-Rl (IX) wherein R is a fatty alcohol of greater than C8; Rl is alkyl of greater than C8 or H; and x represents the number of oxyethylene groups per molecule and is in the range of from about 5 to about 200.
Examples of commercially available products are Alkamus~
products sold by Rhône-Poulenc Inc. and products having a PEG
castor oil CTFA designation; and 10) an ethoxylated fatty alcohol of formula (X):
RO(CH2CH20)X-H (X) wherein R is a fatty alcohol; and x represents the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20 Examples of commercially available products are Rhodasurf~ products sold by Rhône-Poulenc Inc.
~165251 Of the above classes of nonionic surfactants, while not wishing to be bound to any particular theory, it is believed that the surfactants of class 8 may not perform as well as those of the other c lasses.
More preferred nonionic surfactants within the above classes include:
1 ) Those of Formula (I) wherein R is a straight-chain or branched alkyl group having a carbon number of from about 16 to 20, x represents the number of oxyethylene groups per molecule and is in the range o of from about 10 to about 20, and y represents the number of oxypropylene groups per molecule and is in the range of from about 4 to about 8. A commercial example of such a nonionic surfactant is InkMasterTM 750; or wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to 14, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 12, and y represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 6. A commercial example of such a nonionic surfactant is Antarox(~ LA-EP-16, sold by Rhône-Poulenc.;
2) Those of Formula (II) wherein R is a straight-chain or branchedalkyl group having a carbon number of from about 16 to about 20, x and x' represents the number of oxyethylene groups per molecule and is in the range of from about 4 to about 10, and y and y' represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 5;
3) Those of Formula (III) wherein R is a straight-chain or branched alkyl group having a carbon number of from about 12 to about 18, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25, and y represents the number of oxypropylene groups per molecule and is in the range of from -about 2 to about 15. A commercial example of such a nonionic surfactant is Hipochem@~ DI600, sold by High Point Chemicals;
4) Those of Formula (IV) wherein R and R' is H or a branched or s straight-chain having a carbon number of from about 8 to about 14 and x is the number of oxyethylene groups per molecule and is in the range of from about 8 to about 12. A commercial example of such a nomonic surfactant is InkMasterTM 730;
o 5) Those of Formula (V) wherein R' and R" are H or CH2CH2OH or CH2CH(CH3)-OH and R is a fatty alkyl group having a carbon number of from about 8 to about 14;
6) Those of Formula (VI) wherein R is a fatty alkyl group having a carbon number of from about 8 to about 14 and x represents the number of oxyethylene groups per molecule and is in the range of from about 4 to about 8;
7) Those of Formula (IX) wherein R is a fatty alcohol of greater than C8; Rl is alkyl of greater than C8 or H; and x represents the number of oxyethylene groups per molecule and is in the range of from about 8 to about 30; and 8) Those of Formula (X) wherein R is a fatty alcohol having a carbon 2s number from about 12 to about 18, and x represents the number of oxyethylene groups per molecule and is in the range of from about 5 to about 15. A commercial example of such a nonionic surfactant is Rhodasurf(~ BC720, sold by Rhone-Poulenc Inc.;
Of the above, the use of the following classes of nonionic surfactants is particularly suggested: those of Formula (I), (II), (III), (IV), (V), (VI) and (X) as defined above.
The deinking agent is to be applied to wastepaper which is in the form of a pulp, that is, to wastepaper which has first been substantially reduced to individual fibers. Thus the first step in the process of the present invention is to convert wastepaper to a pulp. Pulping can be conducted using any of the various conventional processes and equipment designed for this purpose. Most conveniently, the wastepaper process feedstock is treated in a device known as a"hydrapulper," which produces a slurry of the fibers in water. Preferably the pulping is conducted in a neutral medium. Most preferably, it is conducted without the use of chemical additives, i.e., with only the use of water.
After the pulping step, the resulting fibers are contacted in an aqueous medium with the deinking agent. This contact step can suitably be conducted in the pulping equipment, for instance, by simply adding the deinking agent to the aqueous slurry of the equipment used to pulp the wastepaper, e.g., hyrdrapulper. Alternatively,the contact may be carried out using separate processing equipment which provides for agitation and temperature control of the aqueous pulp slurry.
For the contact step, a sufficient amount of enzyme is utilized to achieve an efficient diffusion rate such that substantially all of the pulp fiber (generally greater than about 70%, preferably greater than about 80% and most preferably greater than about 90%) comes into contact with the enzyme component. Determining a sufficient amount is within the skill of an artisan. The amount of enzyme is generally in the range of from about 0.007% to about 0.056%, preferably from about 0.018% to about 0.029%, and most preferably from about 0.020% to about 2s 0.027%, by weight of the pulp slurry.
A sufficient amount of nonionic surfactant is utilized to achieve applopliate interaction with the enzyme to achieve the synergistic effect. Determining a sufficient amount is within the skill of an artisan. Generally, the range is from about 0.02% to about 0.25%, preferably from about 0.035% to about 0.1% and most preferably from about 0.04% to about 0.075%, by weight of the pulp slurry.
216~2~1 The efficiency of the deinking agent can be significantly influenced by the pH of the pulp slurry during the contact step. Fluctuations in the pH can result in deactivation of the enzyme component of the deinking agent. During addition of the deinking agent and the activation period the pulp slurry can have a pH ranging from about 4 to about 9, preferably about 4 to about 8, more preferably from about 5.5 to about 7.5, even more preferably from about 6 to about 7, and most preferably from about 6.5 to about 7. A neutral pH is preferred. The pulp slurry pH is to be consistent with the activity pH range of the enzyme, preferably the optimal activity pH range of the enzyme. The incorporation of buffering materials such as sodium 0 citrate or sodium phosphate to m~int~in an apl)rol fiate pH is preferred.
It is important to m~int~in an appropriate pulp slurry temperature during the contact step. The temperature is to be consistent with the activity temperature range, preferably the optimal activity t~lllpel~lure range, for the enzyme component of the deinking agent. Fluctuations in temperature can deactivate/denature the enzyme component. Determinin~ the appropriate temperature range is within the skill of an artisan. Generally the range is fromabout 40C to about 65C, preferably from about 45C to about 60C and most preferably from about 52C to about 58C.
The activation period for the deinking agent is the time needed to allow substantially all of the paper fibers in the pulp slurry to come into contact with the deinking agent. Conditions such as the degree of dilution of the pulp slurry and the utilization of agitation can effect the amount of time needed. The determination of the al)plu~liate amount of time needed is within the skill of an artisan. Generally, the activation period can range from about 5 to about 90, preferably from about 10 to about 60 and most preferably from about 15 to about 30 minutes.
The enzyme and nonionic surfactant components of the deinking agent are prepared by conventional means. The enzyme and nonionic surfactant can be combined by mixing prior to addition to the pulped wastepaper slurried in water or the components can be added and mixed into the slurry in any order of addition.
216~2~ 1 In addition to water, pulp and deinking agent, the contact slurry may further comprise substances conventionally employed in deinking processes, e.g., brighteners, solvents, antifoam agents and water softeners. The use of additional deinking agents is neither necessary nor preferred.
The overall deinking process generally comprises pulping or maceration of the wastepaper and ink removal by a flotation system, a water washing system or a combination flotation/water washing system. A screening or coarse cleaning stage0 or stages can be utilized to remove cont~min~nt.~ such as glass, stone, metal and staples. A centrifugal c!eaning stage or stages can be utilized to remove light weight materials such as plastics. Typical deinking processes are described in Fergusen, L.D., "Deinking Chemistry: part 1" July 1992 TAPPI Journal pp. 75 to 83; Ferguson, L.D., "Deinking Chemistry: part 2" August 1992 TAPPI Journal pp.
49-58; and Spielbauer, J.L. "Deinking System Overview", Voith, Inc. Appleton, WI, pp. 1-9. To the extent necessary for completion, these references are expressly incorporated herein by reference.
The preferred deinking process of the present invention comprises the steps of (a) converting the wastepaper to a pulp (preferably when lltili~ing an aqueous medium having from about 10% to about 14% by weight pulp on a dry weight basis); (b) contacting the pulp with a sufficient amount of the deinking agent as defined above in an aqueous medium having a pH of from about 4 to about 9; and (c) removing ink (which is suspended or dispersed) from the pulp by flotation, water-washing, or a combination of flotation and water washing.
During the contacting step, the pulp slurry generally can comprise from about 1.0%
to about 6.0%, preferably from about 1.5% to about 5.5%, more preferably from about 2.5% to about 4.5% and most preferably from about 3.2% to about 3.8%
pulp on a dry weight basis. Before addition, the pulp slurry's pH and temperature should be checked and, if needed, adjusted such that the pH and temperature of the slurry is within the activity ranges for pH and temperature (preferably within the 21652~1 optimal activity ranges) of the enzyme component of the deinking agent.
Preferably after the deinking agent has been added to the pulp slurry and an adequate activation period has been completed, the pH and/or temperature are adjusted via conventional means, e.g., the addition of buffers or addition of heat, for a sufficient period of time to denature the enzyme component of the deinkingagent. Preferably the pH and/or temperature are raised to about 9 for pH and/or about 55C for the temperature to denature the enzyme component. Increasing the pH beyond 9 can cause alkaline darkening and should be avoided.
o As previously indicated, the deinking agent of the present invention can be included in the aqueous liquor (e.g., water) into which the wastepaper is initially pulped; into the aqueous pulp produced after the wastepaper is pulped; or into the flotation cell. Preferably, the deinking agent is incorporated after the wastepaper has been pulped.
The deinking can be conclucted in the presence of additional chemicals however it is pref~ d that the chemicals used consist essentially of the deinking agent, buffers and optionally additional surfactants to aid in the flotation and/or washing steps. Peroxide can be included if desired, however an advantage of the invention is that it is usually unnecessary and is therefore not preferred.
The invention is further defined by the following non-limiting examples.
EXAMPLE I
The following is an example of a laboratory scale deinking process in which xerographically printed paper is recycled using the deinking agent of present invention:
Sample Preparation: To provide a uniform ink concentration in the pulper, a sheet of paper with a known ink concentration is xerographically reproduced multiple 21652~1 times. The identical sheets are then twice passed through a mechanical paper shredder.
Hydrapulping: Hot tap water (50-54C) is added to a FormaxTM 1800H
Adirondack hydrapulper. The xerographic paper is then added to reach a pulp consistency of 14% of pulp fiber by weight of the total aqueous medium. Pulping is conducted at ambient pH (about 9) until the xerographic paper is thoroughly defibered (about 15 minutes).
0 Intermediate Reactor After pulping, a large sample is diluted to about 3.5% by weight pulp consistency and added to a two liter jacketed reactor. The pH is adjusted to about 6.5 using a 10% solution of H2SO4. The temperature of the pulpslurry is raised to about 55C. At a point of uniform mixing and constant pH andtemperature, 0.2% by weight InkMasterTM 750, and 190 ml/ton Novo Nordisk enzyme SP342 on a dry fiber weight basis are added and well mixed at a constant rate for about 20 minutes. After mixing, the pH is adjusted to 9 with a 15.2%
NaOH solution to denature the enzyme.
Flotation Deinking The pulp is diluted to about 1% by weight by taking 1429g of about 3.5% consistency pulp and diluting with hot tap water to a final volume ofabout five liters. The 1% slurry is then added to a Denver Flotation Cell, Model D-l, having a five liter capacity. The pH is then adjusted to about 8.8-9.2 with NaOH. InkMasterTM 750, a nonionic surfactant falling within the scope of Formula(I) at about 0.2% (by weight) is added to the float cell and premixed for about two minutes at an agitation rate of about 2100 rpm. Air is introduced at three liters per minute and continued at that rate for about three minutes. The float rejects arecollected from the cell by ~kimming the foam along the plane of a weir in a consistent manor. The rejects are saved for yield calculations. The slurry rem~ining in the float cell is mixed for about 30 seconds with no air and used as the float accepts.
Samplin~ points A sample for C~n~ n Standard Freeness measurement is taken at the end of the intermediate reactor mixing time. Samples for handsheet preparation are taken after intermediate reactor mixing (float feed sample) and after flotation (float accepts sample). Triplicate sheets are prepared from each sample and are analyzed for dirt count. Two of the three handsheets prepared are then analyzed for brightness. The rem~ining sheet is used to measure tensile strength.
Handsheet Pleparalion The handsheets are made using a TAPPI Standard 159 mm diameter sheet former with stirrer, a TAPPI standard couch roll, and a TAPPI
standard couch plate as described in TAPPI Test Method T 205 om-88. This test method is followed with the following exceptions. The paper is defibered and prepared using the above procedure. The handsheets are pressed using a standard pneumatic press with gauge for about 1.5 minutes at about 50 psi. The sheets aredried in ring stacks overnight under constant temperature and constant humidity conditions.
Testing C~n~ m Standard Freeness testing is conducted following TAPPI
Method T 228 os-58. Brightness testing is performed in duplicate using the Technidyne Handybright brightness meter (based on percent light reflectance at about 457nm). Each handsheet is cut into seven equal pie shaped slices then stacked on top of each other with the wire side up. The central portion of the top slice is measured and then placed at the bottom of the stack. The next slice is measured until all slices are measured. The final brightnes.~ value for each sample is determined by averaging 14 values (two sheets per sample or seven values per sheet). The standard deviation of the 14 values is typically in the range of from about 0.30 to about 0.75.
The handsheets are evaluated for ink content using an image analysis system. Fifty random fields having an area of approximately 35 mm2 per field are evaluated persheet so that the total area assessed is about 1750 mm2 per sheet. Analysis is conducted using a Leco 2001 Image Analysis System. Dirt count, in parts per million, is determined for particles larger than about 0.0025 mm2.
~1652~1 The handsheets are evaluated for strength properties using TAPPI Standard Test Method T494 om-88, "Tensile Breaking properties of Paper and Paperboard" with some modifications. Handsheets are kept in a constant temperature and humidity s chamber until testing. Then, each sheet is cut into seven strips measuring about 15 mm x 110 mm. Each strip is then evaluated using an Instron Tensile Strength testing machine and an average tensile index is determined.
The results of these tests are presented in Table I.
EXAMPLE II
The procedure of Example I is repeated with the exception that no enzyme or surfactant is added to the intermediate reactor. This provides a control experiment for the experiments involving the SP342 enzyme. The results are presented in Table I.
EXAMPLE III
The procedure of Exampl I is repeated with the exception that about 63 ml/ton ofSP342 is added to the intermediate reactor. No surfactant is added to the intermediate reactor. The results are presented in Table I.
EXAMPLE IV
2s The procedure of Example I is repeated with the exception that about 190 ml/ton SP342 is added to the intermediate reactor. No surfactant is added to the intermediate reactor. The results are presented in Table I.
EXAMPLE V
The procedure of Example I is repeated with the exception that about 450 ml/ton SP342 is added to the intermediate reactor. No surfactant is added to the intermediate reactor. The results are presented in Table I.
EXAMPLE VI
o The procedure of Example I is repeated with the exception that the pH in the intermediate reactor is adjusted to about 7.0 and Denimax L at about 253 ml/ton is substituted as the added enzyme. InkMasterTM 750 is added at about 0.2% to the intermediate reactor as well. The results are presented in Table I.
EXAMPLE VII
The procedure of Example I is repeated with the exception that the pH in the intermediate reactor is adjusted to about 7.0 and no surfactant or enzyme is added.
This provides a control run for the experiments involving Denimax L enzyme. The results are presented in Table I.
EXAMPLE VIII
The procedure of Example I is repeated with the exception that the pH in the 2s intermediate reactor is adjusted to about 7.0 and about 63 ml/ton Denimax L is added. No surfactant is added to the intermediate reactor. The results are presented in Table I.
EXAMPLE IX
The procedure of Example I is repeated with the exception that the pH in the intermediate reactor is adjusted to about 7.0 and about 253 ml/ton Denimax L is added. No surfactant is added to the intermediate reactor. The results are presented in Table I.
EXAMPLE X
s The procedure of Example I is repeated with the exception that the pH in the intermediate reactor is adjusted to about 7.0 and about 450 ml/ton Denimax L is added. No surfactant is added to the intermediate reactor. The results are presented in Table I.
EXAMPLE XI
The following is an example of a pilot scale deinking process of the present invention: A pilot scale trial is conducted using Novo Nordisk enzyme SP342 with InkMasterTM 750 vs. a control (no enzyme; InkMasterTM 750 only) to determine if enhanced dirt removal, as observed in the lab, can be achieved on this scale. The experiments involve repulping mixed office wastepaper (MOW)) with about 70% xerographic content at about 10% pulp consistency for about 30 minutes at ambient pH (about 7.88) and at a temperature of about 50C. The stockis then diluted to about 3.5% pulp consistency and the pH and temperature are adjusted to about 6.5 and about 55 C respectively. At this point, about 2 lb/ton InkMasterTM 750 is added for the control run (Example I) and about 2 Ib/ton InkMasterTM 750 plus 190 ml/ton SP342 is added for the enzyme run (Example II).
This slurry is allowed to mix for about 20 minutes in each experiment. The slurry 2s is then reduced to about 1 % pulp consistency and an additional 1 lb/ton InkMasterTM 750 is added and mixed prior to flotation. The stock is then cycled for 6 passes through a Voith deinking flotation cell. After 6 passes, the float accepts are thickened on a sidehill screen. Brightness pads are made from samples taken at float cell feed, float cell accepts at half and full-time, and sidehill screen accepts. Brightness measurements are made in triplicate and indicate a two pointgain with enzyme vs. the Control. C~n~ n Standard Freeness is measured in duplicate at the float cell feed following the 3.5% consistency step. The values are equivalent for both runs at 356 ml. Handsheets are made from the same stock as brightness pads for dirt count determination (five sheets/sample). Dirt counts are measured and percent dirt removal vs. process stage is evaluated. The run using enzyme plus surfactant treatment shows a 26% increase in dirt removal vs. the control for both half-time float accept and full-time float accept stages. A 31%increase in dirt removal is observed with enzyme treatment vs. the control at the side-hill accept stage. The results of these tests are presented in Table I, and are illustrated in Figures 1-3.
o E a~ ~ a7 . ~ a~ . a~ N N ) a~
~ ~ r` <D O O O tD N ~ D O _ O U~
_, O
2 ~ _ N ~ -- _ O X ~ 0 N O ~t U~
~5 E
U~ O ~ _ ID N ~ i 1~ ai N _ N -- 0 N a) N ~ N O) _ ~
m ~ 0 o N ~ a7 ~ N ~
o .
O ,~
E e ~ e N ~ N ~ ~ N
x ~ ~ ' ~ ' u ' x ~ ' 2 1 6525 ~
o ~D
rY ~; N
Z . e ~O 0 ~ _ rND tD CD
r~ ~ .
rl J
O X
n D N ~O N
O o a~
~L ~L
O > > ~ >
> ~ a~ .~ .c X ' ' ~ ~
c E
8, . . _ o , r ~
Z ,, ,, ~ r ~ a; . E
IJJ ~ ~ T ~ ,~
EXAMPLE XII
The procedure of Example I is repeated with the exceptions that the intermediates reactor and float cell volumes are increased to 4 liter and 12 liter respectively, that 0.05% InkMasterTM 730 is used in the intermediate reactor and flotation steps and that sampling points are at 0.5 minute intervals during flotation and that only ink removal by dirt count measurement is assessed. Ink removal results are presentedin Table II.
EXAMPLE XIII
The procedure of Example XII is repeated with the exceptions that no enzyme is added to the intermediate reactor, thereby, providing a control experiment. Ink removal results are presented in Table II.
EXAMPLE XIV
The procedure of Example I is repeated with the exceptions that the intermediatereactor and float cell volumes are increased to 4 liter and 12 liter respectively, that 0.025% Alkamide~ DC-212/S is used in the intermediate reactor and flotation steps and that sampling points are at 0.5 minute intervals during flotation and that only ink removal by dirt count measurement is assessed. Ink removal results are presented in Table II.
2s EXAMPLE XV
The procedure of Example XIV is repeated with the exceptions that no enzyme is added to the intermediate reactor, thereby, providing a control experiment. Ink removal results are presented in Table II.
EXAMPLE XVI
The procedure of Example I is repeated with the exceptions that the intermediatereactor and float cell volumes are increased to 4 liter and 12 liter respectively, that 0.05% Alkamide~ C-5 is used in the intermediate reactor and float steps and thatsampling points are at 0.5 minute intervals during flotation and that only ink removal by dirt count measurement is assessed. Ink removal results are presentedin Table II.
lo EXAMPLE XVII
The procedure of Example XVI is repeated with the exception that no enzyme is added to the intermediate reactor, thereby, providing a control experiment. Ink removal results are presented in Table II.
Ink Removal (%) Fl~ lion Time (min) Example Xll Example Xlll Example XIV ' ,rle XV Example XVI Example XVII
0.5 58.3 54.8 47.8 50.6 48.9 46.7 1.0 78.7 70.1 71.8 67.9 63.3 ` 69.3 1.5 83.0 79.6 83.8 82.1 77.9 76.1 2.0 91.0 87.9 89.6 88.5 85.8 82.0 2.5 94.0 92.1 91.8 89.8 87.6 84.7 EXAMPLE XVIII
The procedure of Example I is repeated with the exceptions that the intermediatereactor and float cell volumes are increased to 4 liter and 12 liter respectively, that 0.03% Rhodasurf~ BC720 is used in the intermediate reactor and float steps and that sampling points are at 0.5 minute intervals during flotation and that only ink removal by dirt count measurement is assessed. Ink removal results are presentedin Table III.
2s EXAMPLE XIX
The procedure of Example XVIII is repeated with the exception that no enzyme is added to the intermediate reactor, thereby, providing a control experiment. Ink s removal results are presented in Table III.
EXAMPLE XX
The procedure of Example I is repeated with the exceptions that the intermediatelo reactor and float cell volumes are increased to 4 liter and 12 liter respectively, that 0.2% and 0.055% Hipocl;em~ DI-600 is used in the intermediate reactor and float steps respectively and that sampling points are at 0.5 minute intervals during flotation and that only ink removal by dirt count measurement is assessed. Ink removal results are presented in Table III.
EXAMPLE XXI
The procedure of Example XX is repeated with the exception that no enzyme is added to the intermediate reactor, thereby, providing a control experiment. Inlcremoval results are presented in Table III.
EXAMPLE XXII
The procedure of Example I is repeated with the exceptions that the intermediatereactor and float cell volumes are increased to 4 liter and 12 liter respectively, that 0.05% and 0.055% Antarox~ LA-EP-16 is used in the intermediate reactor and float steps respectively and that sampling points are at 0.5 minute intervals during flotation and that only ink removal by dirt count measurement is assessed. Ink removal results are presented in Table III.
- ~16~2~:1 EXAMPLE XXIII
The procedure of Example XXII is repeated with the exception that no enzyme is s added to the intermediate reactor, thereby, providing a control experiment. Ink removal results are presented in Table III.
Ink Removal (%) rl~ lion Time (min) Ex.l~"r~e XVIII Example XIX Example XX Example XXI Example XXII F ~r~e XXIII
0.5 56.8 48.9 74.8 68.1 56.9 53.1 1.0 76.7 68.6 78.8 70.5 67.1 71.9 1.5 84.9 83.2 77.7 68.7 77.5 74.9 2.0 90.4 89.4 75.8 65.1 82.4 77.7 2.5 94.4 92.2 75.3 65.9 84.3 80.9 o The preferred embodiments have been described in detail herein above for the purpose of illustration only. It will be appalellt to a practitioner of ordinary skill in the art that various modifications could be made to the above described exampleswithout departing from the spirit and scope of the invention as defined in the claims set forth hereinafter.
R-C(O)O-(CH2CH2O)x-Rl (IX) wherein R is a fatty alcohol of greater than C8; Rl is alkyl of greater than C8 or H; and x represents the number of oxyethylene groups per molecule and is in the range of from about 5 to about 200.
Examples of commercially available products are Alkamus~
products sold by Rhône-Poulenc Inc. and products having a PEG
castor oil CTFA designation; and 10) an ethoxylated fatty alcohol of formula (X):
RO(CH2CH20)X-H (X) wherein R is a fatty alcohol; and x represents the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20 Examples of commercially available products are Rhodasurf~ products sold by Rhône-Poulenc Inc.
~165251 Of the above classes of nonionic surfactants, while not wishing to be bound to any particular theory, it is believed that the surfactants of class 8 may not perform as well as those of the other c lasses.
More preferred nonionic surfactants within the above classes include:
1 ) Those of Formula (I) wherein R is a straight-chain or branched alkyl group having a carbon number of from about 16 to 20, x represents the number of oxyethylene groups per molecule and is in the range o of from about 10 to about 20, and y represents the number of oxypropylene groups per molecule and is in the range of from about 4 to about 8. A commercial example of such a nonionic surfactant is InkMasterTM 750; or wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to 14, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 12, and y represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 6. A commercial example of such a nonionic surfactant is Antarox(~ LA-EP-16, sold by Rhône-Poulenc.;
2) Those of Formula (II) wherein R is a straight-chain or branchedalkyl group having a carbon number of from about 16 to about 20, x and x' represents the number of oxyethylene groups per molecule and is in the range of from about 4 to about 10, and y and y' represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 5;
3) Those of Formula (III) wherein R is a straight-chain or branched alkyl group having a carbon number of from about 12 to about 18, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25, and y represents the number of oxypropylene groups per molecule and is in the range of from -about 2 to about 15. A commercial example of such a nonionic surfactant is Hipochem@~ DI600, sold by High Point Chemicals;
4) Those of Formula (IV) wherein R and R' is H or a branched or s straight-chain having a carbon number of from about 8 to about 14 and x is the number of oxyethylene groups per molecule and is in the range of from about 8 to about 12. A commercial example of such a nomonic surfactant is InkMasterTM 730;
o 5) Those of Formula (V) wherein R' and R" are H or CH2CH2OH or CH2CH(CH3)-OH and R is a fatty alkyl group having a carbon number of from about 8 to about 14;
6) Those of Formula (VI) wherein R is a fatty alkyl group having a carbon number of from about 8 to about 14 and x represents the number of oxyethylene groups per molecule and is in the range of from about 4 to about 8;
7) Those of Formula (IX) wherein R is a fatty alcohol of greater than C8; Rl is alkyl of greater than C8 or H; and x represents the number of oxyethylene groups per molecule and is in the range of from about 8 to about 30; and 8) Those of Formula (X) wherein R is a fatty alcohol having a carbon 2s number from about 12 to about 18, and x represents the number of oxyethylene groups per molecule and is in the range of from about 5 to about 15. A commercial example of such a nonionic surfactant is Rhodasurf(~ BC720, sold by Rhone-Poulenc Inc.;
Of the above, the use of the following classes of nonionic surfactants is particularly suggested: those of Formula (I), (II), (III), (IV), (V), (VI) and (X) as defined above.
The deinking agent is to be applied to wastepaper which is in the form of a pulp, that is, to wastepaper which has first been substantially reduced to individual fibers. Thus the first step in the process of the present invention is to convert wastepaper to a pulp. Pulping can be conducted using any of the various conventional processes and equipment designed for this purpose. Most conveniently, the wastepaper process feedstock is treated in a device known as a"hydrapulper," which produces a slurry of the fibers in water. Preferably the pulping is conducted in a neutral medium. Most preferably, it is conducted without the use of chemical additives, i.e., with only the use of water.
After the pulping step, the resulting fibers are contacted in an aqueous medium with the deinking agent. This contact step can suitably be conducted in the pulping equipment, for instance, by simply adding the deinking agent to the aqueous slurry of the equipment used to pulp the wastepaper, e.g., hyrdrapulper. Alternatively,the contact may be carried out using separate processing equipment which provides for agitation and temperature control of the aqueous pulp slurry.
For the contact step, a sufficient amount of enzyme is utilized to achieve an efficient diffusion rate such that substantially all of the pulp fiber (generally greater than about 70%, preferably greater than about 80% and most preferably greater than about 90%) comes into contact with the enzyme component. Determining a sufficient amount is within the skill of an artisan. The amount of enzyme is generally in the range of from about 0.007% to about 0.056%, preferably from about 0.018% to about 0.029%, and most preferably from about 0.020% to about 2s 0.027%, by weight of the pulp slurry.
A sufficient amount of nonionic surfactant is utilized to achieve applopliate interaction with the enzyme to achieve the synergistic effect. Determining a sufficient amount is within the skill of an artisan. Generally, the range is from about 0.02% to about 0.25%, preferably from about 0.035% to about 0.1% and most preferably from about 0.04% to about 0.075%, by weight of the pulp slurry.
216~2~1 The efficiency of the deinking agent can be significantly influenced by the pH of the pulp slurry during the contact step. Fluctuations in the pH can result in deactivation of the enzyme component of the deinking agent. During addition of the deinking agent and the activation period the pulp slurry can have a pH ranging from about 4 to about 9, preferably about 4 to about 8, more preferably from about 5.5 to about 7.5, even more preferably from about 6 to about 7, and most preferably from about 6.5 to about 7. A neutral pH is preferred. The pulp slurry pH is to be consistent with the activity pH range of the enzyme, preferably the optimal activity pH range of the enzyme. The incorporation of buffering materials such as sodium 0 citrate or sodium phosphate to m~int~in an apl)rol fiate pH is preferred.
It is important to m~int~in an appropriate pulp slurry temperature during the contact step. The temperature is to be consistent with the activity temperature range, preferably the optimal activity t~lllpel~lure range, for the enzyme component of the deinking agent. Fluctuations in temperature can deactivate/denature the enzyme component. Determinin~ the appropriate temperature range is within the skill of an artisan. Generally the range is fromabout 40C to about 65C, preferably from about 45C to about 60C and most preferably from about 52C to about 58C.
The activation period for the deinking agent is the time needed to allow substantially all of the paper fibers in the pulp slurry to come into contact with the deinking agent. Conditions such as the degree of dilution of the pulp slurry and the utilization of agitation can effect the amount of time needed. The determination of the al)plu~liate amount of time needed is within the skill of an artisan. Generally, the activation period can range from about 5 to about 90, preferably from about 10 to about 60 and most preferably from about 15 to about 30 minutes.
The enzyme and nonionic surfactant components of the deinking agent are prepared by conventional means. The enzyme and nonionic surfactant can be combined by mixing prior to addition to the pulped wastepaper slurried in water or the components can be added and mixed into the slurry in any order of addition.
216~2~ 1 In addition to water, pulp and deinking agent, the contact slurry may further comprise substances conventionally employed in deinking processes, e.g., brighteners, solvents, antifoam agents and water softeners. The use of additional deinking agents is neither necessary nor preferred.
The overall deinking process generally comprises pulping or maceration of the wastepaper and ink removal by a flotation system, a water washing system or a combination flotation/water washing system. A screening or coarse cleaning stage0 or stages can be utilized to remove cont~min~nt.~ such as glass, stone, metal and staples. A centrifugal c!eaning stage or stages can be utilized to remove light weight materials such as plastics. Typical deinking processes are described in Fergusen, L.D., "Deinking Chemistry: part 1" July 1992 TAPPI Journal pp. 75 to 83; Ferguson, L.D., "Deinking Chemistry: part 2" August 1992 TAPPI Journal pp.
49-58; and Spielbauer, J.L. "Deinking System Overview", Voith, Inc. Appleton, WI, pp. 1-9. To the extent necessary for completion, these references are expressly incorporated herein by reference.
The preferred deinking process of the present invention comprises the steps of (a) converting the wastepaper to a pulp (preferably when lltili~ing an aqueous medium having from about 10% to about 14% by weight pulp on a dry weight basis); (b) contacting the pulp with a sufficient amount of the deinking agent as defined above in an aqueous medium having a pH of from about 4 to about 9; and (c) removing ink (which is suspended or dispersed) from the pulp by flotation, water-washing, or a combination of flotation and water washing.
During the contacting step, the pulp slurry generally can comprise from about 1.0%
to about 6.0%, preferably from about 1.5% to about 5.5%, more preferably from about 2.5% to about 4.5% and most preferably from about 3.2% to about 3.8%
pulp on a dry weight basis. Before addition, the pulp slurry's pH and temperature should be checked and, if needed, adjusted such that the pH and temperature of the slurry is within the activity ranges for pH and temperature (preferably within the 21652~1 optimal activity ranges) of the enzyme component of the deinking agent.
Preferably after the deinking agent has been added to the pulp slurry and an adequate activation period has been completed, the pH and/or temperature are adjusted via conventional means, e.g., the addition of buffers or addition of heat, for a sufficient period of time to denature the enzyme component of the deinkingagent. Preferably the pH and/or temperature are raised to about 9 for pH and/or about 55C for the temperature to denature the enzyme component. Increasing the pH beyond 9 can cause alkaline darkening and should be avoided.
o As previously indicated, the deinking agent of the present invention can be included in the aqueous liquor (e.g., water) into which the wastepaper is initially pulped; into the aqueous pulp produced after the wastepaper is pulped; or into the flotation cell. Preferably, the deinking agent is incorporated after the wastepaper has been pulped.
The deinking can be conclucted in the presence of additional chemicals however it is pref~ d that the chemicals used consist essentially of the deinking agent, buffers and optionally additional surfactants to aid in the flotation and/or washing steps. Peroxide can be included if desired, however an advantage of the invention is that it is usually unnecessary and is therefore not preferred.
The invention is further defined by the following non-limiting examples.
EXAMPLE I
The following is an example of a laboratory scale deinking process in which xerographically printed paper is recycled using the deinking agent of present invention:
Sample Preparation: To provide a uniform ink concentration in the pulper, a sheet of paper with a known ink concentration is xerographically reproduced multiple 21652~1 times. The identical sheets are then twice passed through a mechanical paper shredder.
Hydrapulping: Hot tap water (50-54C) is added to a FormaxTM 1800H
Adirondack hydrapulper. The xerographic paper is then added to reach a pulp consistency of 14% of pulp fiber by weight of the total aqueous medium. Pulping is conducted at ambient pH (about 9) until the xerographic paper is thoroughly defibered (about 15 minutes).
0 Intermediate Reactor After pulping, a large sample is diluted to about 3.5% by weight pulp consistency and added to a two liter jacketed reactor. The pH is adjusted to about 6.5 using a 10% solution of H2SO4. The temperature of the pulpslurry is raised to about 55C. At a point of uniform mixing and constant pH andtemperature, 0.2% by weight InkMasterTM 750, and 190 ml/ton Novo Nordisk enzyme SP342 on a dry fiber weight basis are added and well mixed at a constant rate for about 20 minutes. After mixing, the pH is adjusted to 9 with a 15.2%
NaOH solution to denature the enzyme.
Flotation Deinking The pulp is diluted to about 1% by weight by taking 1429g of about 3.5% consistency pulp and diluting with hot tap water to a final volume ofabout five liters. The 1% slurry is then added to a Denver Flotation Cell, Model D-l, having a five liter capacity. The pH is then adjusted to about 8.8-9.2 with NaOH. InkMasterTM 750, a nonionic surfactant falling within the scope of Formula(I) at about 0.2% (by weight) is added to the float cell and premixed for about two minutes at an agitation rate of about 2100 rpm. Air is introduced at three liters per minute and continued at that rate for about three minutes. The float rejects arecollected from the cell by ~kimming the foam along the plane of a weir in a consistent manor. The rejects are saved for yield calculations. The slurry rem~ining in the float cell is mixed for about 30 seconds with no air and used as the float accepts.
Samplin~ points A sample for C~n~ n Standard Freeness measurement is taken at the end of the intermediate reactor mixing time. Samples for handsheet preparation are taken after intermediate reactor mixing (float feed sample) and after flotation (float accepts sample). Triplicate sheets are prepared from each sample and are analyzed for dirt count. Two of the three handsheets prepared are then analyzed for brightness. The rem~ining sheet is used to measure tensile strength.
Handsheet Pleparalion The handsheets are made using a TAPPI Standard 159 mm diameter sheet former with stirrer, a TAPPI standard couch roll, and a TAPPI
standard couch plate as described in TAPPI Test Method T 205 om-88. This test method is followed with the following exceptions. The paper is defibered and prepared using the above procedure. The handsheets are pressed using a standard pneumatic press with gauge for about 1.5 minutes at about 50 psi. The sheets aredried in ring stacks overnight under constant temperature and constant humidity conditions.
Testing C~n~ m Standard Freeness testing is conducted following TAPPI
Method T 228 os-58. Brightness testing is performed in duplicate using the Technidyne Handybright brightness meter (based on percent light reflectance at about 457nm). Each handsheet is cut into seven equal pie shaped slices then stacked on top of each other with the wire side up. The central portion of the top slice is measured and then placed at the bottom of the stack. The next slice is measured until all slices are measured. The final brightnes.~ value for each sample is determined by averaging 14 values (two sheets per sample or seven values per sheet). The standard deviation of the 14 values is typically in the range of from about 0.30 to about 0.75.
The handsheets are evaluated for ink content using an image analysis system. Fifty random fields having an area of approximately 35 mm2 per field are evaluated persheet so that the total area assessed is about 1750 mm2 per sheet. Analysis is conducted using a Leco 2001 Image Analysis System. Dirt count, in parts per million, is determined for particles larger than about 0.0025 mm2.
~1652~1 The handsheets are evaluated for strength properties using TAPPI Standard Test Method T494 om-88, "Tensile Breaking properties of Paper and Paperboard" with some modifications. Handsheets are kept in a constant temperature and humidity s chamber until testing. Then, each sheet is cut into seven strips measuring about 15 mm x 110 mm. Each strip is then evaluated using an Instron Tensile Strength testing machine and an average tensile index is determined.
The results of these tests are presented in Table I.
EXAMPLE II
The procedure of Example I is repeated with the exception that no enzyme or surfactant is added to the intermediate reactor. This provides a control experiment for the experiments involving the SP342 enzyme. The results are presented in Table I.
EXAMPLE III
The procedure of Exampl I is repeated with the exception that about 63 ml/ton ofSP342 is added to the intermediate reactor. No surfactant is added to the intermediate reactor. The results are presented in Table I.
EXAMPLE IV
2s The procedure of Example I is repeated with the exception that about 190 ml/ton SP342 is added to the intermediate reactor. No surfactant is added to the intermediate reactor. The results are presented in Table I.
EXAMPLE V
The procedure of Example I is repeated with the exception that about 450 ml/ton SP342 is added to the intermediate reactor. No surfactant is added to the intermediate reactor. The results are presented in Table I.
EXAMPLE VI
o The procedure of Example I is repeated with the exception that the pH in the intermediate reactor is adjusted to about 7.0 and Denimax L at about 253 ml/ton is substituted as the added enzyme. InkMasterTM 750 is added at about 0.2% to the intermediate reactor as well. The results are presented in Table I.
EXAMPLE VII
The procedure of Example I is repeated with the exception that the pH in the intermediate reactor is adjusted to about 7.0 and no surfactant or enzyme is added.
This provides a control run for the experiments involving Denimax L enzyme. The results are presented in Table I.
EXAMPLE VIII
The procedure of Example I is repeated with the exception that the pH in the 2s intermediate reactor is adjusted to about 7.0 and about 63 ml/ton Denimax L is added. No surfactant is added to the intermediate reactor. The results are presented in Table I.
EXAMPLE IX
The procedure of Example I is repeated with the exception that the pH in the intermediate reactor is adjusted to about 7.0 and about 253 ml/ton Denimax L is added. No surfactant is added to the intermediate reactor. The results are presented in Table I.
EXAMPLE X
s The procedure of Example I is repeated with the exception that the pH in the intermediate reactor is adjusted to about 7.0 and about 450 ml/ton Denimax L is added. No surfactant is added to the intermediate reactor. The results are presented in Table I.
EXAMPLE XI
The following is an example of a pilot scale deinking process of the present invention: A pilot scale trial is conducted using Novo Nordisk enzyme SP342 with InkMasterTM 750 vs. a control (no enzyme; InkMasterTM 750 only) to determine if enhanced dirt removal, as observed in the lab, can be achieved on this scale. The experiments involve repulping mixed office wastepaper (MOW)) with about 70% xerographic content at about 10% pulp consistency for about 30 minutes at ambient pH (about 7.88) and at a temperature of about 50C. The stockis then diluted to about 3.5% pulp consistency and the pH and temperature are adjusted to about 6.5 and about 55 C respectively. At this point, about 2 lb/ton InkMasterTM 750 is added for the control run (Example I) and about 2 Ib/ton InkMasterTM 750 plus 190 ml/ton SP342 is added for the enzyme run (Example II).
This slurry is allowed to mix for about 20 minutes in each experiment. The slurry 2s is then reduced to about 1 % pulp consistency and an additional 1 lb/ton InkMasterTM 750 is added and mixed prior to flotation. The stock is then cycled for 6 passes through a Voith deinking flotation cell. After 6 passes, the float accepts are thickened on a sidehill screen. Brightness pads are made from samples taken at float cell feed, float cell accepts at half and full-time, and sidehill screen accepts. Brightness measurements are made in triplicate and indicate a two pointgain with enzyme vs. the Control. C~n~ n Standard Freeness is measured in duplicate at the float cell feed following the 3.5% consistency step. The values are equivalent for both runs at 356 ml. Handsheets are made from the same stock as brightness pads for dirt count determination (five sheets/sample). Dirt counts are measured and percent dirt removal vs. process stage is evaluated. The run using enzyme plus surfactant treatment shows a 26% increase in dirt removal vs. the control for both half-time float accept and full-time float accept stages. A 31%increase in dirt removal is observed with enzyme treatment vs. the control at the side-hill accept stage. The results of these tests are presented in Table I, and are illustrated in Figures 1-3.
o E a~ ~ a7 . ~ a~ . a~ N N ) a~
~ ~ r` <D O O O tD N ~ D O _ O U~
_, O
2 ~ _ N ~ -- _ O X ~ 0 N O ~t U~
~5 E
U~ O ~ _ ID N ~ i 1~ ai N _ N -- 0 N a) N ~ N O) _ ~
m ~ 0 o N ~ a7 ~ N ~
o .
O ,~
E e ~ e N ~ N ~ ~ N
x ~ ~ ' ~ ' u ' x ~ ' 2 1 6525 ~
o ~D
rY ~; N
Z . e ~O 0 ~ _ rND tD CD
r~ ~ .
rl J
O X
n D N ~O N
O o a~
~L ~L
O > > ~ >
> ~ a~ .~ .c X ' ' ~ ~
c E
8, . . _ o , r ~
Z ,, ,, ~ r ~ a; . E
IJJ ~ ~ T ~ ,~
EXAMPLE XII
The procedure of Example I is repeated with the exceptions that the intermediates reactor and float cell volumes are increased to 4 liter and 12 liter respectively, that 0.05% InkMasterTM 730 is used in the intermediate reactor and flotation steps and that sampling points are at 0.5 minute intervals during flotation and that only ink removal by dirt count measurement is assessed. Ink removal results are presentedin Table II.
EXAMPLE XIII
The procedure of Example XII is repeated with the exceptions that no enzyme is added to the intermediate reactor, thereby, providing a control experiment. Ink removal results are presented in Table II.
EXAMPLE XIV
The procedure of Example I is repeated with the exceptions that the intermediatereactor and float cell volumes are increased to 4 liter and 12 liter respectively, that 0.025% Alkamide~ DC-212/S is used in the intermediate reactor and flotation steps and that sampling points are at 0.5 minute intervals during flotation and that only ink removal by dirt count measurement is assessed. Ink removal results are presented in Table II.
2s EXAMPLE XV
The procedure of Example XIV is repeated with the exceptions that no enzyme is added to the intermediate reactor, thereby, providing a control experiment. Ink removal results are presented in Table II.
EXAMPLE XVI
The procedure of Example I is repeated with the exceptions that the intermediatereactor and float cell volumes are increased to 4 liter and 12 liter respectively, that 0.05% Alkamide~ C-5 is used in the intermediate reactor and float steps and thatsampling points are at 0.5 minute intervals during flotation and that only ink removal by dirt count measurement is assessed. Ink removal results are presentedin Table II.
lo EXAMPLE XVII
The procedure of Example XVI is repeated with the exception that no enzyme is added to the intermediate reactor, thereby, providing a control experiment. Ink removal results are presented in Table II.
Ink Removal (%) Fl~ lion Time (min) Example Xll Example Xlll Example XIV ' ,rle XV Example XVI Example XVII
0.5 58.3 54.8 47.8 50.6 48.9 46.7 1.0 78.7 70.1 71.8 67.9 63.3 ` 69.3 1.5 83.0 79.6 83.8 82.1 77.9 76.1 2.0 91.0 87.9 89.6 88.5 85.8 82.0 2.5 94.0 92.1 91.8 89.8 87.6 84.7 EXAMPLE XVIII
The procedure of Example I is repeated with the exceptions that the intermediatereactor and float cell volumes are increased to 4 liter and 12 liter respectively, that 0.03% Rhodasurf~ BC720 is used in the intermediate reactor and float steps and that sampling points are at 0.5 minute intervals during flotation and that only ink removal by dirt count measurement is assessed. Ink removal results are presentedin Table III.
2s EXAMPLE XIX
The procedure of Example XVIII is repeated with the exception that no enzyme is added to the intermediate reactor, thereby, providing a control experiment. Ink s removal results are presented in Table III.
EXAMPLE XX
The procedure of Example I is repeated with the exceptions that the intermediatelo reactor and float cell volumes are increased to 4 liter and 12 liter respectively, that 0.2% and 0.055% Hipocl;em~ DI-600 is used in the intermediate reactor and float steps respectively and that sampling points are at 0.5 minute intervals during flotation and that only ink removal by dirt count measurement is assessed. Ink removal results are presented in Table III.
EXAMPLE XXI
The procedure of Example XX is repeated with the exception that no enzyme is added to the intermediate reactor, thereby, providing a control experiment. Inlcremoval results are presented in Table III.
EXAMPLE XXII
The procedure of Example I is repeated with the exceptions that the intermediatereactor and float cell volumes are increased to 4 liter and 12 liter respectively, that 0.05% and 0.055% Antarox~ LA-EP-16 is used in the intermediate reactor and float steps respectively and that sampling points are at 0.5 minute intervals during flotation and that only ink removal by dirt count measurement is assessed. Ink removal results are presented in Table III.
- ~16~2~:1 EXAMPLE XXIII
The procedure of Example XXII is repeated with the exception that no enzyme is s added to the intermediate reactor, thereby, providing a control experiment. Ink removal results are presented in Table III.
Ink Removal (%) rl~ lion Time (min) Ex.l~"r~e XVIII Example XIX Example XX Example XXI Example XXII F ~r~e XXIII
0.5 56.8 48.9 74.8 68.1 56.9 53.1 1.0 76.7 68.6 78.8 70.5 67.1 71.9 1.5 84.9 83.2 77.7 68.7 77.5 74.9 2.0 90.4 89.4 75.8 65.1 82.4 77.7 2.5 94.4 92.2 75.3 65.9 84.3 80.9 o The preferred embodiments have been described in detail herein above for the purpose of illustration only. It will be appalellt to a practitioner of ordinary skill in the art that various modifications could be made to the above described exampleswithout departing from the spirit and scope of the invention as defined in the claims set forth hereinafter.
Claims (17)
1. A method for deinking office wastepaper comprising the steps of:
a) converting wastepaper to a pulp;
b) contacting the pulp with a deinking agent comprising:
i) an enzyme active at a pH of from about 4 to about 9 and;
ii) a nonionic surfactant selected from the group consisting of higher aliphatic alcohol alkoxylates, aliphatic acid alkoxylates, higher aromatic alcohol alkoxylates, fatty acid amides of alkanolamines, fatty acid amide alkoxylates, propylene glycol alkoxylates, block or random copolymers of ethylene and propylene oxide, higher alcohol polyethylene polypropylene block or random adducts and mixtures thereof;
in an aqueous medium having a pH of from about 4 to about 9;
c) removing ink from the pulp.
a) converting wastepaper to a pulp;
b) contacting the pulp with a deinking agent comprising:
i) an enzyme active at a pH of from about 4 to about 9 and;
ii) a nonionic surfactant selected from the group consisting of higher aliphatic alcohol alkoxylates, aliphatic acid alkoxylates, higher aromatic alcohol alkoxylates, fatty acid amides of alkanolamines, fatty acid amide alkoxylates, propylene glycol alkoxylates, block or random copolymers of ethylene and propylene oxide, higher alcohol polyethylene polypropylene block or random adducts and mixtures thereof;
in an aqueous medium having a pH of from about 4 to about 9;
c) removing ink from the pulp.
2. A method according to Claim 1 wherein the enzyme is active at a pH of from about 4 to about 8.
3. A method according to Claim 2 wherein the nonionic surfactant is selected from the group consisting of:
a) a fatty alcohol having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, alkoxylated with ethylene oxide and propylene oxide of the formula (I) R-O-(CH2CH2O)x-(CH2CH(CH3)-O)y-H; (I) wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25, preferably between about 10 and about 20, and y represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 10, preferably between about 4 and about 8;
b) a fatty alcohol having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, alkoxylated with ethylene oxide and propylene oxide of the formula:
R-O-(CH2CH2O)x-(CH2CH(CH3)-O)y-(CH2CH2O)x'-(CH2CH(CH3)-O)y'-H;
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, x and x', which may be the same or different, represents the number of oxyethylene groups per molecule and is in the range of from about 2 to about 25, preferably between about 4 and about 10, and y and y', which may be the same or different, represents the number of oxypropylene groups per molecule and is in the range of from 0 to about 10, preferably between about 1 to about 5;
c) a fatty acid having a carbon number of from about 8 to about 22, preferably from about 12 to about 18, alkoxylated with ethylene oxide and propylene oxide of the formula:
R-C(O)O-(CH2CH2O)x-(CH2CH(CH3)-O)y-H;
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably from about 12 to about 18, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25, and y represents the number of oxypropylene groups per molecule and is in the range of from about 2 to about 15;
d) an aromatic alcohol having alkyl chain(s) with a carbon number of from about 8 to about 20, preferably between 8 and about 14, alkoxylated with ethylene oxide of the formula:
wherein R and R is H or an alkyl group and the alkyl is branched or straight-chain having a carbon number of from about 8 to about 20, preferably between 8 and about 14, x is the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20, preferably between about 8 to about 12;
e) a fatty amide of alkanolamide of the formula:
wherein R' and R" are H or CH2CH2OH or CH2CH(CH3)-OH and R is a fatty alkyl group having a carbon number of from about 8 to about 20, preferably of from about 8 to about 14;
f) an alkoxylated fatty acid amide of alkanolamide of the formula:
wherein R is a fatty alkyl group having a carbon number of from about 8 to about 20, preferably from about 8 to about 14, and x represents the number of oxyethylene groups per molecule and is in the range of from about 2 to about 10, preferably from about 4 to about 8;
g) a propylene glycol alkoxylate of the formula:
HO-(CH2CH2O)o(CH2CH(CH3)-O)m(CH2CH2O)p-H
wherein o and p are the number of oxyethylene groups per molecule and are in the range of from about 3 to about 15 and m is number of oxypropylene groups per molecule and is in the range of from about 25 to about 40;
h) a block or random copolymer of ethylene and propylene oxide of the formula:
HO (CH(CH3)CH2O)m(CH2CH2O)p(CH(CH3)CH2O)nH
wherein m and n are the number of oxypropylene groups per molecule and are in the range of from about 10 to about 25 and p is the number of oxyethylene groups per molecule and is in the range of from about 5 to about 25;
i) an ethoxylated fatty acid, glycol and polyethylene glycol esters of the formula:
R-C(O)O-(CH2CH2O)x-R1 wherein R is a fatty alcohol greater than C8, R1 is an alkyl of greater than C8 or H, and x represents the number of oxyethylene groups per molecule and is in the range of from about 5 to about 200, preferably of from about 8 to about 30; and j) an ethoxylated fatty alcohol of the formula:
RO(CH2CH2O)x-H
wherein R is a fatty alcohol, preferably straight-chained or branched alkyl group having a carbon number of from about 12 to about 18, and x represents the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20, preferably from about 5 to about 15.
a) a fatty alcohol having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, alkoxylated with ethylene oxide and propylene oxide of the formula (I) R-O-(CH2CH2O)x-(CH2CH(CH3)-O)y-H; (I) wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25, preferably between about 10 and about 20, and y represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 10, preferably between about 4 and about 8;
b) a fatty alcohol having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, alkoxylated with ethylene oxide and propylene oxide of the formula:
R-O-(CH2CH2O)x-(CH2CH(CH3)-O)y-(CH2CH2O)x'-(CH2CH(CH3)-O)y'-H;
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, x and x', which may be the same or different, represents the number of oxyethylene groups per molecule and is in the range of from about 2 to about 25, preferably between about 4 and about 10, and y and y', which may be the same or different, represents the number of oxypropylene groups per molecule and is in the range of from 0 to about 10, preferably between about 1 to about 5;
c) a fatty acid having a carbon number of from about 8 to about 22, preferably from about 12 to about 18, alkoxylated with ethylene oxide and propylene oxide of the formula:
R-C(O)O-(CH2CH2O)x-(CH2CH(CH3)-O)y-H;
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably from about 12 to about 18, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25, and y represents the number of oxypropylene groups per molecule and is in the range of from about 2 to about 15;
d) an aromatic alcohol having alkyl chain(s) with a carbon number of from about 8 to about 20, preferably between 8 and about 14, alkoxylated with ethylene oxide of the formula:
wherein R and R is H or an alkyl group and the alkyl is branched or straight-chain having a carbon number of from about 8 to about 20, preferably between 8 and about 14, x is the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20, preferably between about 8 to about 12;
e) a fatty amide of alkanolamide of the formula:
wherein R' and R" are H or CH2CH2OH or CH2CH(CH3)-OH and R is a fatty alkyl group having a carbon number of from about 8 to about 20, preferably of from about 8 to about 14;
f) an alkoxylated fatty acid amide of alkanolamide of the formula:
wherein R is a fatty alkyl group having a carbon number of from about 8 to about 20, preferably from about 8 to about 14, and x represents the number of oxyethylene groups per molecule and is in the range of from about 2 to about 10, preferably from about 4 to about 8;
g) a propylene glycol alkoxylate of the formula:
HO-(CH2CH2O)o(CH2CH(CH3)-O)m(CH2CH2O)p-H
wherein o and p are the number of oxyethylene groups per molecule and are in the range of from about 3 to about 15 and m is number of oxypropylene groups per molecule and is in the range of from about 25 to about 40;
h) a block or random copolymer of ethylene and propylene oxide of the formula:
HO (CH(CH3)CH2O)m(CH2CH2O)p(CH(CH3)CH2O)nH
wherein m and n are the number of oxypropylene groups per molecule and are in the range of from about 10 to about 25 and p is the number of oxyethylene groups per molecule and is in the range of from about 5 to about 25;
i) an ethoxylated fatty acid, glycol and polyethylene glycol esters of the formula:
R-C(O)O-(CH2CH2O)x-R1 wherein R is a fatty alcohol greater than C8, R1 is an alkyl of greater than C8 or H, and x represents the number of oxyethylene groups per molecule and is in the range of from about 5 to about 200, preferably of from about 8 to about 30; and j) an ethoxylated fatty alcohol of the formula:
RO(CH2CH2O)x-H
wherein R is a fatty alcohol, preferably straight-chained or branched alkyl group having a carbon number of from about 12 to about 18, and x represents the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20, preferably from about 5 to about 15.
4. A method according to Claim 3 wherein the enzyme is a cellulase.
5. A method according to Claim 4 wherein the ink is removed from the pulp by flotation, water washing or a combination of flotation and water washing.
6. A method according to Claim 3 wherein the nonionic surfactant is represented by formula (I) wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 14, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 12, and y represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 6.
7. A method for deinking office wastepaper comprising the steps of:
a) converting the office wastepaper to a pulp in water such that the resulting aqueous medium consists essentially of from about 10% to about 14% on a dry weight basis pulp and the remainder water;
b) diluting the aqueous medium with water until the aqueous medium consists essentially of from about 1% to about 6% on a dry weight basis pulp and the remainder water;
c) contacting the aqueous medium for a sufficient amount of time with a sufficient amount of deinking agent comprising:
i) an enzyme active at a pH of from about 4 to about 9; and ii) a nonionic surfactant selected from the group consisting of higher aliphatic alcohol alkoxylates, aliphatic acid alkoxylates, higher aromatic alcohol alkoxylates, fatty acid amides of alkanolamines, fatty acid amide alkoxylates, propylene glycol alkoxylates, block or random copolymers of ethylene and propylene oxide, higher alcohol polyethylene polypropylene block or random adducts and mixtures thereof;
wherein said aqueous medium has a pH of from about 4 to about 9 and a temperature consistent with the optimal activity of the enzyme;
d) adjusting the pH or temperature to denature the enzyme; and e) removing ink from the aqueous medium by flotation, water washing or a combination of flotation and water washing.
a) converting the office wastepaper to a pulp in water such that the resulting aqueous medium consists essentially of from about 10% to about 14% on a dry weight basis pulp and the remainder water;
b) diluting the aqueous medium with water until the aqueous medium consists essentially of from about 1% to about 6% on a dry weight basis pulp and the remainder water;
c) contacting the aqueous medium for a sufficient amount of time with a sufficient amount of deinking agent comprising:
i) an enzyme active at a pH of from about 4 to about 9; and ii) a nonionic surfactant selected from the group consisting of higher aliphatic alcohol alkoxylates, aliphatic acid alkoxylates, higher aromatic alcohol alkoxylates, fatty acid amides of alkanolamines, fatty acid amide alkoxylates, propylene glycol alkoxylates, block or random copolymers of ethylene and propylene oxide, higher alcohol polyethylene polypropylene block or random adducts and mixtures thereof;
wherein said aqueous medium has a pH of from about 4 to about 9 and a temperature consistent with the optimal activity of the enzyme;
d) adjusting the pH or temperature to denature the enzyme; and e) removing ink from the aqueous medium by flotation, water washing or a combination of flotation and water washing.
8. A method according to Claim 7 wherein the enzyme is active at a pH of from about 4 to about 8.
9. A method according to Claim 7 wherein the nonionic surfactant is selected from the group consisting of:
a) a fatty alcohol having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, alkoxylated with ethylene oxide and propylene oxide of the formula (I) R-O-(CH2CH2O)x-(CH2CH(CH3)-O)y-H; (I) wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25, preferably between about 10 and about 20, and y represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 10, preferably between about 4 and about 8;
b) a fatty alcohol having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, alkoxylated with ethylene oxide and propylene oxide of the formula:
R-O-(CH2CH2O)x-(CH2CH(CH3)-O)y-(CH2CH2O)x'(CH2CH(CH3)-O)y'-H;
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, x and x', which may be the same or different, represents the number of oxyethylene groups per molecule and is in the range of from about 2 to about 25, preferably between about 4 and about 10, and y and y', which may be the same or different, represents the number of oxypropylene groups per molecule and is in the range of from 0 to about 10, preferably between about 1 to about 5;
c) a fatty acid having a carbon number of from about 8 to about 22, preferably from about 12 to about 18, alkoxylated with ethylene oxide and propylene oxide of the formula:
R-C(O)O-(CH2CH2O)x-(CH2CH(CH3)-O)y -H;
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably from about 12 to about 18, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25, and y represents the number of oxypropylene groups per molecule and is in the range of from about 2 to about 15;
d) an aromatic alcohol having alkyl chain(s) with a carbon number of from about 8 to about 20, preferably between 8 and about 14, alkoxylated with ethylene oxide of the formula:
wherein R and R is H or an alkyl group and the alkyl is branched or straight-chain having a carbon number of from about 8 to about 20, preferably between 8 and about 14, x is the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20, preferably between about 8 to about 12;
e) a fatty amide of alkanolamide of the formula:
wherein R' and R" are H or CH2CH2OH or CH2CH(CH3)-OH and R is a fatty alkyl group having a carbon number of from about 8 to about 20, preferably of from about 8 to about 14;
f) an alkoxylated fatty acid amide of alkanolamide of the formula:
wherein R is a fatty alkyl group having a carbon number of from about 8 to about 20, preferably from about 8 to about 14, and x represents the number of oxyethylene groups per molecule and is in the range of from about 2 to about 10, preferably from about 4 to about 8;
g) a propylene glycol alkoxylate of the formula:
HO-(CH2CH2O)o(CH2CH(CH3)-O)m(CH2CH2O)p-H
wherein o and p are the number of oxyethylene groups per molecule and are in the range of from about 3 to about 15 and m is number of oxypropylene groups per molecule and is in the range of from about 25 to about 40;
h) a block or random copolymer of ethylene and propylene oxide of the formula:
HO (CH(CH3)CH2O)m(CH2CH2O)p(CH(CH3)CH2O)nH
wherein m and n are the number of oxypropylene groups per molecule and are in the range of from about 10 to about 25 and p is the number of oxyethylene groups per molecule and is in the range of from about 5 to about 25;
i) an ethoxylated fatty acid, glycol and polyethylene glycol esters of the formula:
R-C(O)O-(CH2CH2O)x-R1 wherein R is a fatty alcohol greater than C8, R1 is an alkyl of greater than C8 or H, and x represents the number of oxyethylene groups per molecule and is in the range of from about 5 to about 200, preferably of from about 8 to about 30; and j) an ethoxylated fatty alcohol of the formula:
RO(CH2CH2O)x-H
wherein R is a fatty alcohol, preferably straight-chained or branched alkyl group having a carbon number of from about 12 to about 18, and x represents the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20, preferably from about 5 to about 15.
a) a fatty alcohol having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, alkoxylated with ethylene oxide and propylene oxide of the formula (I) R-O-(CH2CH2O)x-(CH2CH(CH3)-O)y-H; (I) wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25, preferably between about 10 and about 20, and y represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 10, preferably between about 4 and about 8;
b) a fatty alcohol having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, alkoxylated with ethylene oxide and propylene oxide of the formula:
R-O-(CH2CH2O)x-(CH2CH(CH3)-O)y-(CH2CH2O)x'(CH2CH(CH3)-O)y'-H;
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, x and x', which may be the same or different, represents the number of oxyethylene groups per molecule and is in the range of from about 2 to about 25, preferably between about 4 and about 10, and y and y', which may be the same or different, represents the number of oxypropylene groups per molecule and is in the range of from 0 to about 10, preferably between about 1 to about 5;
c) a fatty acid having a carbon number of from about 8 to about 22, preferably from about 12 to about 18, alkoxylated with ethylene oxide and propylene oxide of the formula:
R-C(O)O-(CH2CH2O)x-(CH2CH(CH3)-O)y -H;
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably from about 12 to about 18, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25, and y represents the number of oxypropylene groups per molecule and is in the range of from about 2 to about 15;
d) an aromatic alcohol having alkyl chain(s) with a carbon number of from about 8 to about 20, preferably between 8 and about 14, alkoxylated with ethylene oxide of the formula:
wherein R and R is H or an alkyl group and the alkyl is branched or straight-chain having a carbon number of from about 8 to about 20, preferably between 8 and about 14, x is the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20, preferably between about 8 to about 12;
e) a fatty amide of alkanolamide of the formula:
wherein R' and R" are H or CH2CH2OH or CH2CH(CH3)-OH and R is a fatty alkyl group having a carbon number of from about 8 to about 20, preferably of from about 8 to about 14;
f) an alkoxylated fatty acid amide of alkanolamide of the formula:
wherein R is a fatty alkyl group having a carbon number of from about 8 to about 20, preferably from about 8 to about 14, and x represents the number of oxyethylene groups per molecule and is in the range of from about 2 to about 10, preferably from about 4 to about 8;
g) a propylene glycol alkoxylate of the formula:
HO-(CH2CH2O)o(CH2CH(CH3)-O)m(CH2CH2O)p-H
wherein o and p are the number of oxyethylene groups per molecule and are in the range of from about 3 to about 15 and m is number of oxypropylene groups per molecule and is in the range of from about 25 to about 40;
h) a block or random copolymer of ethylene and propylene oxide of the formula:
HO (CH(CH3)CH2O)m(CH2CH2O)p(CH(CH3)CH2O)nH
wherein m and n are the number of oxypropylene groups per molecule and are in the range of from about 10 to about 25 and p is the number of oxyethylene groups per molecule and is in the range of from about 5 to about 25;
i) an ethoxylated fatty acid, glycol and polyethylene glycol esters of the formula:
R-C(O)O-(CH2CH2O)x-R1 wherein R is a fatty alcohol greater than C8, R1 is an alkyl of greater than C8 or H, and x represents the number of oxyethylene groups per molecule and is in the range of from about 5 to about 200, preferably of from about 8 to about 30; and j) an ethoxylated fatty alcohol of the formula:
RO(CH2CH2O)x-H
wherein R is a fatty alcohol, preferably straight-chained or branched alkyl group having a carbon number of from about 12 to about 18, and x represents the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20, preferably from about 5 to about 15.
10. A method according to Claim 7 wherein the enzyme is a cellulase.
11. A method according to Claim 7 wherein the aqueous medium of the contacting step has a temperature of from about 40°C to abut 65°C and the deinking agent remains in contact with the aqueous medium for from about 5 minutes to abut 90 minutes.
12. A method according to Claim 7 wherein the nonionic surfactant is represented by formula (I) wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 14, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 12, and y represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 6.
13. A deinking agent for office wastepaper comprising:
i) an enzyme active at a pH of from about 4 to about 9; and ii) a nonionic surfactant selected from the group consisting of higher aliphatic alcohol alkoxylates, aliphatic acid alkoxylates, higher aromatic alcohol alkoxylates, fatty acid amides of alkanolamines, fatty acid amide alkoxylates, propylene glycol alkoxylates, block or random copolymers of ethylene and propylene oxide, higher alcohol polyethylene polypropylene block or random adducts and mixtures thereof;
i) an enzyme active at a pH of from about 4 to about 9; and ii) a nonionic surfactant selected from the group consisting of higher aliphatic alcohol alkoxylates, aliphatic acid alkoxylates, higher aromatic alcohol alkoxylates, fatty acid amides of alkanolamines, fatty acid amide alkoxylates, propylene glycol alkoxylates, block or random copolymers of ethylene and propylene oxide, higher alcohol polyethylene polypropylene block or random adducts and mixtures thereof;
14. A deinking agent according to Claim 13 wherein the enzyme is active at a pH of from about 4 to about 8, more preferably from about 5.5 to about 7.5, most preferably from about 6 to about 7.
15. A deinking agent according to Claim 13 wherein the enzyme is a cellulase enzyme.
16. A deinking agent according to Claim 13 wherein the nonionic surfactant is selected from the group consisting of:
a) a fatty alcohol having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, alkoxylated with ethylene oxide and propylene oxide of the formula (I) R-O-(CH2CH2O)x-(CH2CH(CH3)-O)y-H; (I) wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25, preferably between about 10 and about 20, and y represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 10, preferably between about 4 and about 8;
b) a fatty alcohol having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, alkoxylated with ethylene oxide and propylene oxide of the formula:
R-O-(CH2CH2O)x-(CH2CH(CH3)-O)y-(CH2CH2O)x'-(CH2CH(CH3)-O)y'-H;
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, x and x', which may be the same or different, represents the number of oxyethylene groups per molecule and is in the range of from about 2 to about 25, preferably between about 4 and about 10, and y and y', which may be the same or different, represents the number of oxypropylene groups per molecule and is in the range of from 0 to about 10, preferably between about 1 to about 5;
c) a fatty acid having a carbon number of from about 8 to about 22, preferably from about 12 to about 18, alkoxylated with ethylene oxide and propylene oxide of the formula:
R-C(O)O-(CH2CH2O)x-(CH2CH(CH3)-O)y-H;
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably from about 12 to about 18, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25, and y represents the number of oxypropylene groups per molecule and is in the range of from about 2 to about 15;
d) an aromatic alcohol having alkyl chain(s) with a carbon number of from about 8 to about 20, preferably between 8 and about 14, alkoxylated with ethylene oxide of the formula:
wherein R and R is H or an alkyl group and the alkyl is branched or straight-chain having a carbon number of from about 8 to about 20, preferably between 8 and about 14, x is the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20, preferably between about 8 to about 12;
e) a fatty amide of alkanolamide of the formula:
wherein R' and R" are H or CH2CH2OH or CH2CH(CH3)-OH and R is a fatty alkyl group having a carbon number of from about 8 to about 20, preferably of from about 8 to about 14;
f) an alkoxylated fatty acid amide of alkanolamide of the formula:
wherein R is a fatty alkyl group having a carbon number of from about 8 to about 20, preferably from about 8 to about 14, and x represents the number of oxyethylene groups per molecule and is in the range of from about 2 to about 10, preferably from about 4 to about 8;
g) a propylene glycol alkoxylate of the formula:
HO-(CH2CH2O)o (CH2CH(CH3)-o)m(CH2CH2O)p-H
wherein o and p are the number of oxyethylene groups per molecule and are in the range of from about 3 to about 15 and m is number of oxypropylene groups per molecule and is in the range of from about 25 to about 40;
h) a block or random copolymer of ethylene and propylene oxide of the formula:
HO (CH(CH3)CH2O)m (CH2CH2O)p (CH(CH3)CH2O)nH
wherein m and n are the number of oxypropylene groups per molecule and are in the range of from about 10 to about 25 and p is the number of oxyethylene groups per molecule and is in the range of from about 5 to about 25;
i) an ethoxylated fatty acid, glycol and polyethylene glycol esters of the formula:
R-C(O)O-(CH2CH2O)x-R1 wherein R is a fatty alcohol greater than C8, R1 is an alkyl of greater than C8 or H, and x represents the number of oxyethylene groups per molecule and is in the range of from about 5 to about 200, preferably of from about 8 to about 30; and j) an ethoxylated fatty alcohol of the formula:
RO(CH2CH2O)x-H
wherein R is a fatty alcohol, preferably straight-chained or branched alkyl group having a carbon number of from about 12 to about 18, and x represents the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20, preferably from about 5 to about 15.
a) a fatty alcohol having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, alkoxylated with ethylene oxide and propylene oxide of the formula (I) R-O-(CH2CH2O)x-(CH2CH(CH3)-O)y-H; (I) wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25, preferably between about 10 and about 20, and y represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 10, preferably between about 4 and about 8;
b) a fatty alcohol having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, alkoxylated with ethylene oxide and propylene oxide of the formula:
R-O-(CH2CH2O)x-(CH2CH(CH3)-O)y-(CH2CH2O)x'-(CH2CH(CH3)-O)y'-H;
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably between about 16 and about 20, x and x', which may be the same or different, represents the number of oxyethylene groups per molecule and is in the range of from about 2 to about 25, preferably between about 4 and about 10, and y and y', which may be the same or different, represents the number of oxypropylene groups per molecule and is in the range of from 0 to about 10, preferably between about 1 to about 5;
c) a fatty acid having a carbon number of from about 8 to about 22, preferably from about 12 to about 18, alkoxylated with ethylene oxide and propylene oxide of the formula:
R-C(O)O-(CH2CH2O)x-(CH2CH(CH3)-O)y-H;
wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 22, preferably from about 12 to about 18, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 25, and y represents the number of oxypropylene groups per molecule and is in the range of from about 2 to about 15;
d) an aromatic alcohol having alkyl chain(s) with a carbon number of from about 8 to about 20, preferably between 8 and about 14, alkoxylated with ethylene oxide of the formula:
wherein R and R is H or an alkyl group and the alkyl is branched or straight-chain having a carbon number of from about 8 to about 20, preferably between 8 and about 14, x is the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20, preferably between about 8 to about 12;
e) a fatty amide of alkanolamide of the formula:
wherein R' and R" are H or CH2CH2OH or CH2CH(CH3)-OH and R is a fatty alkyl group having a carbon number of from about 8 to about 20, preferably of from about 8 to about 14;
f) an alkoxylated fatty acid amide of alkanolamide of the formula:
wherein R is a fatty alkyl group having a carbon number of from about 8 to about 20, preferably from about 8 to about 14, and x represents the number of oxyethylene groups per molecule and is in the range of from about 2 to about 10, preferably from about 4 to about 8;
g) a propylene glycol alkoxylate of the formula:
HO-(CH2CH2O)o (CH2CH(CH3)-o)m(CH2CH2O)p-H
wherein o and p are the number of oxyethylene groups per molecule and are in the range of from about 3 to about 15 and m is number of oxypropylene groups per molecule and is in the range of from about 25 to about 40;
h) a block or random copolymer of ethylene and propylene oxide of the formula:
HO (CH(CH3)CH2O)m (CH2CH2O)p (CH(CH3)CH2O)nH
wherein m and n are the number of oxypropylene groups per molecule and are in the range of from about 10 to about 25 and p is the number of oxyethylene groups per molecule and is in the range of from about 5 to about 25;
i) an ethoxylated fatty acid, glycol and polyethylene glycol esters of the formula:
R-C(O)O-(CH2CH2O)x-R1 wherein R is a fatty alcohol greater than C8, R1 is an alkyl of greater than C8 or H, and x represents the number of oxyethylene groups per molecule and is in the range of from about 5 to about 200, preferably of from about 8 to about 30; and j) an ethoxylated fatty alcohol of the formula:
RO(CH2CH2O)x-H
wherein R is a fatty alcohol, preferably straight-chained or branched alkyl group having a carbon number of from about 12 to about 18, and x represents the number of oxyethylene groups per molecule and is in the range of from about 1 to about 20, preferably from about 5 to about 15.
17. A deinking agent according to Claim 13 wherein the nonionic surfactant is of formula (I) wherein R is a straight-chain or branched alkyl group having a carbon number of from about 8 to about 14, x represents the number of oxyethylene groups per molecule and is in the range of from about 3 to about 12, and y represents the number of oxypropylene groups per molecule and is in the range of from about 1 to about 6.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US35669594A | 1994-12-15 | 1994-12-15 | |
| US08/356,695 | 1994-12-15 | ||
| US41024295A | 1995-03-24 | 1995-03-24 | |
| US08/410,242 | 1995-03-24 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2165251A1 true CA2165251A1 (en) | 1996-06-16 |
Family
ID=26999337
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2165251 Abandoned CA2165251A1 (en) | 1994-12-15 | 1995-12-14 | Deinking composition and process |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US5807464A (en) |
| EP (1) | EP0717144A1 (en) |
| JP (1) | JPH08226088A (en) |
| AU (1) | AU701773B2 (en) |
| CA (1) | CA2165251A1 (en) |
| NZ (1) | NZ280682A (en) |
Families Citing this family (24)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3568700B2 (en) * | 1996-05-30 | 2004-09-22 | 第一工業製薬株式会社 | Nonionic surfactant |
| DE19700253A1 (en) * | 1997-01-07 | 1998-07-09 | Henkel Kgaa | Process for removing capsule oils from carbonless paper |
| AU6046199A (en) | 1998-09-17 | 2000-04-03 | Novozymes North America, Inc. | Methods for deinking and decolorizing printed paper |
| DE19855326A1 (en) * | 1998-12-01 | 2000-06-08 | Cognis Deutschland Gmbh | Process for removing printing inks from printed waste paper |
| US6784146B1 (en) * | 2000-10-27 | 2004-08-31 | Kemira Chemicals, Inc. | Deinking method and composition for wastepaper |
| US6666950B2 (en) | 2001-11-28 | 2003-12-23 | Basf Ag | Process for deinking paper using a triglyceride |
| US7645358B2 (en) | 2002-03-25 | 2010-01-12 | Council Of Scientific And Industrial Research | Process for biological deinking of office waste paper |
| US7169257B2 (en) | 2003-11-12 | 2007-01-30 | Kemira Chemicals, Inc. | Method of deinking waste paper using a reduced alkali system |
| US20070040700A1 (en) * | 2004-03-24 | 2007-02-22 | Bachelder Aaron D | Cellular-based preemption system |
| SE532396C2 (en) * | 2005-08-05 | 2010-01-12 | Council Scient Ind Res | Process for enzymatic decolorization of printed paper |
| ATE514561T1 (en) * | 2008-03-31 | 2011-07-15 | Agfa Graphics Nv | METHOD FOR TREATING A LITHOGRAPHIC PRINTING PLATE |
| WO2010093233A1 (en) * | 2009-02-12 | 2010-08-19 | Universiti Sains Malaysia | A process for bioenzymatic deinking of paper |
| US8317973B2 (en) | 2009-11-11 | 2012-11-27 | Kemira Chemical, Inc. | Polyester surfactants for deinking |
| EP2580388B1 (en) * | 2010-06-08 | 2018-01-17 | Buckman Laboratories International, Inc | Methods to degrade sludge from pulp and paper manufacturing |
| CN103314060A (en) * | 2010-09-28 | 2013-09-18 | 陶氏环球技术有限责任公司 | Deinking compositions and methods of use |
| US10681914B2 (en) | 2012-05-29 | 2020-06-16 | Neozyme International, Inc. | Non-toxic plant agent compositions and methods and uses thereof |
| US10557234B2 (en) | 2012-05-29 | 2020-02-11 | Neozyme International, Inc. | Papermaking additive compositions and methods and uses thereof |
| US10334856B2 (en) | 2012-05-29 | 2019-07-02 | Neozyme International, Inc. | Non-toxic pest control compositions and methods and uses thereof |
| CN103396697B (en) * | 2013-05-31 | 2014-08-06 | 威尔（福建）生物有限公司 | Low-foaming liquid polyether waste paper deinking agent and synthetic method thereof |
| JP2015196932A (en) * | 2014-04-03 | 2015-11-09 | ライオン株式会社 | Deinking agent for floatation and manufacturing method of recycled pulp |
| MX2018002205A (en) * | 2015-08-22 | 2018-05-15 | Neozyme Int Inc | Papermaking additive compositions and methods and uses thereof. |
| CN105386352B (en) * | 2015-11-17 | 2018-05-04 | 江南大学 | It is a kind of to utilize cutinase and the method for the common deinking of chemical reagent |
| CN105566997A (en) * | 2015-11-27 | 2016-05-11 | 徐州工程学院 | Waste paper deinking agent and preparation method and application thereof |
| CN109306634A (en) * | 2018-08-28 | 2019-02-05 | 广州骏能生物技术有限公司 | A kind of paper product degradation agent, preparation method and its application |
Family Cites Families (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS599299A (en) * | 1982-07-07 | 1984-01-18 | 花王株式会社 | Deinking agent for regenerating used paper |
| US4561933A (en) * | 1983-10-17 | 1985-12-31 | Shell Oil Company | Xerographics deinking |
| US4618400A (en) * | 1984-12-28 | 1986-10-21 | Shell Oil Company | Wastepaper deinking process |
| US4666558A (en) * | 1985-12-11 | 1987-05-19 | Shell Oil Company | Process for newspaper deinking using low-foaming surfactant deinking agent |
| KR960016598B1 (en) * | 1989-05-16 | 1996-12-16 | 재단법인 한국화학연구소 | Biological de-inking method |
| DK80290D0 (en) * | 1990-03-29 | 1990-03-29 | Novo Nordisk As | |
| JP2859393B2 (en) * | 1990-07-24 | 1999-02-17 | ノボ ノルディスク アクティーゼルスカブ | Cellulase and method for producing the same |
| US5248388A (en) * | 1991-04-25 | 1993-09-28 | Betz Paperchem, Inc. | Use of surfactants having an HLB less than 10 in the deinking of dry toner electrostatic printed wastepaper |
| US5227019A (en) * | 1991-07-31 | 1993-07-13 | Shell Oil Company | Wastepaper deinking process |
| US5417808A (en) * | 1991-08-30 | 1995-05-23 | Lion Corporation | Deinking composition for flotation and deinking method |
| US5225046A (en) * | 1992-02-26 | 1993-07-06 | Shell Oil Company | Wastepaper deinking process |
| GB9208293D0 (en) * | 1992-04-15 | 1992-06-03 | Allied Colloids Ltd | Treatment of cellulosic material and compositions for use in this |
| US5258099A (en) * | 1992-07-17 | 1993-11-02 | Shell Oil Company | Office wastepaper deinking process using fatty alcohols |
| DK131193D0 (en) * | 1993-11-23 | 1993-11-23 | Novo Nordisk As |
-
1995
- 1995-12-14 CA CA 2165251 patent/CA2165251A1/en not_active Abandoned
- 1995-12-15 EP EP19950402824 patent/EP0717144A1/en not_active Withdrawn
- 1995-12-15 JP JP32758095A patent/JPH08226088A/en not_active Withdrawn
- 1995-12-15 NZ NZ280682A patent/NZ280682A/en unknown
- 1995-12-15 AU AU40483/95A patent/AU701773B2/en not_active Ceased
-
1997
- 1997-02-03 US US08/794,131 patent/US5807464A/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH08226088A (en) | 1996-09-03 |
| AU4048395A (en) | 1996-06-20 |
| NZ280682A (en) | 1996-09-25 |
| US5807464A (en) | 1998-09-15 |
| EP0717144A1 (en) | 1996-06-19 |
| AU701773B2 (en) | 1999-02-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5807464A (en) | Enzymatic deinking process for office wastepaper with selected noninic surfactants | |
| US4561933A (en) | Xerographics deinking | |
| US5225046A (en) | Wastepaper deinking process | |
| US4666558A (en) | Process for newspaper deinking using low-foaming surfactant deinking agent | |
| US4618400A (en) | Wastepaper deinking process | |
| US5227019A (en) | Wastepaper deinking process | |
| US4586982A (en) | Process for the de-inking of printed waste paper | |
| US5259969A (en) | Deinking of impact and non-impact printed paper | |
| US5718801A (en) | Method for controlling froth and reducing stickies in the flotation process for deinking waste paper using a froth moderating agent | |
| US5817212A (en) | Deinking composition and process | |
| US5248388A (en) | Use of surfactants having an HLB less than 10 in the deinking of dry toner electrostatic printed wastepaper | |
| US5258099A (en) | Office wastepaper deinking process using fatty alcohols | |
| EP0677123B1 (en) | Deinking of printed paper by agglomeration process | |
| CA2199745A1 (en) | Deinking composition and method for deinking waste paper | |
| US5384010A (en) | Deinking wastepaper printed with water-based ink | |
| US5385639A (en) | Deinking wastepaper printed with oil-based ink | |
| JPH06257083A (en) | Deinking agent and method for deinking by flotation using the same deinking agent | |
| US5885413A (en) | Deinking wastepaper containing electrostatic printed ink using branched alcohol alkoxylate surfactant | |
| CA2065712A1 (en) | Process and composition for deinking dry toner electrostatic printed wastepaper | |
| US5660683A (en) | Process for deinking waste paper using a mixture of thiol ethoxylate and alcohol alkoxylates | |
| Sykes et al. | Enzymatic Removal of Stickle Contaminants | |
| Lee et al. | Enzymatic Deinking of Old Newsprit with Alkalophilic Enzymes from Coprinus cinereus 2249 | |
| Rushing et al. | Hydrogen peroxide bleaching of enzyme deinked old newsprint | |
| WO1997018348A1 (en) | Process for enhancing ash removal in deinking process | |
| WO1997022750A2 (en) | Office wastepaper deinking process |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |