CA1314357C - Water treatment polymer - Google Patents
Water treatment polymerInfo
- Publication number
- CA1314357C CA1314357C CA000556224A CA556224A CA1314357C CA 1314357 C CA1314357 C CA 1314357C CA 000556224 A CA000556224 A CA 000556224A CA 556224 A CA556224 A CA 556224A CA 1314357 C CA1314357 C CA 1314357C
- Authority
- CA
- Canada
- Prior art keywords
- acid
- acrylic acid
- copolymer
- sulfato
- polymer
- 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.)
- Expired - Fee Related
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F5/00—Softening water; Preventing scale; Adding scale preventatives or scale removers to water, e.g. adding sequestering agents
- C02F5/08—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents
- C02F5/10—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances
- C02F5/12—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances containing nitrogen
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F5/00—Softening water; Preventing scale; Adding scale preventatives or scale removers to water, e.g. adding sequestering agents
- C02F5/08—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents
- C02F5/10—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances
Abstract
ABSTRACT
Aqueous media are treated to reduce or prevent the deposition of solid material therein comprising the addition to the water of an effective amount of at least one polymer or copolymer formed from a --monomer of the following general structure:
where R1 is independently H or CH3; X is (CH2)n with n an integer of 0 or 1 or
Aqueous media are treated to reduce or prevent the deposition of solid material therein comprising the addition to the water of an effective amount of at least one polymer or copolymer formed from a --monomer of the following general structure:
where R1 is independently H or CH3; X is (CH2)n with n an integer of 0 or 1 or
Description
:L31~357 ~TER TREATMENT POL~ER
The present invention relates to a method for controlling the formation and deposition of scale forming salts in aqueous media. The polymers diselosed herein also find use as part of a corrosion control system to maintain solubilization of the corrosion inhibitors such as zinc and phosphate compounds.
Deposits in cooling waters are classified into two categories -foulants and scales. Foulants usually result from suspended solids in the system and are high in organics. Scales on the other hand are hard, adherent mineral deposits that precipitate from solution. Foulants can usually be removed by pre-treatment of the cooling water, sueh as by filtration. It is the prevention of deposition of scale with which the present invention is primarily concerned.
The problems associated with mineral sealing in cooling water systems have been known for many years. In such syste~s water flowing around heat exchange equipment deposlts mineral scale on the surface of the installation. This scale builds up in layers giving an insulation effect, reducing the heat transfer of the apparatus and also resulting in poor water cireulation. Eventually this neeessitates the shut-down of the unit b~ allow me hanical or ch mical cleaning.
., . ; ~ '' ' ~ ' ,' , .
~ 3 ~
Depositions in lines, heat exchange equipment, etc., may originate from several causes. For example, the precipitation of calcium carbonate and calcium phosphate will form scale, but prcducts of corrosion also result in a deposit of iron oxide salts. These are deposited as scales due to changes in temperature, pH, concentration, pressure and ; inccmpatible water additives.
The development of high pH and/or non-chromate corrosion programs has increased the potential for scale formation due to chemical precipitation.
In particular, since most of the treatments currently used include phosphate and¦or phosphonic acid compounds, the reversion of the polyphosphates and the organic p~losphates plus the use of high alkaline operating conditions leads to the formation and deposition of highly insoluble calcium phosphate.
Although steam generating systems are different from cooling-water ~ - ~
systems, they share common problems relating to calcium phosphate and iro~n - --oxide formation and other mineral scale deposition~ In this regard, the ~ formation of scale and sludge deposits on boiler heating surfaces is the - most serious water problem encountered in steam generation. Although current industrial steam producing systems make use of external treatments of the boiler feed water to reduce scale forming ions, those operations are not totally effective and do not provide adequate treatment sinoe muds, sludge, silts and hardness-imparting ions are not treated thereby, and eventually are introduced into the steam generating system.
Accordingly, internal treatment, i.e., the use of solubilizing chemicals which have the ability to keep the scale-forming materials in solution at concentrations substantially higher than would be expected are used throughout the industry in an attempt to alleviate the problems - ~31~357 encountered by such scale deposit1on. Such solubilizing chemicals include alginates, lignins, lignosulfonates, tannins, carboxymethyl cellulose materials, and synthetic polymers such as polyacrylates and polymethacrylates. Since most of the solubilizing chemicals used are effective for only one or two of the scale forming salts, it is necessary to usc a mixture of chemicals in order to pro~ide adequate scale prevention in these aqueous systems. Thus, depending upon the chemicals present, it may be necessary to employ polymer dispersants to control calcium sulfate and calcium phosphate with organo-phosphorous chemicals used to disperse calcium carbonate. Further, the presence of iron oxide or other materials may additionally reduce the action of the scale prevention chemicals being utilized.
Plthough the foregoing is directed for the most part to cooling water systems and steam generating systems, the same problems occur in scrubber systems and the like. Any aqueous system having calcium and magnesium cations and the exemplified anions, in particular phosphate, will experience the for~.atlon and deposition of the scaling salts.
A further need for water treatment polymers such as are disclosed herein arises in the case of corrosion control systems where there has been an increasing enphasis on the use of high pH and/or non-chrcmate agents such as those utilizing phosphate and/or zinc. These latter materials have~limited solubility and it has been found necessary to add other chemicals to the systems in order to maintain the solubility thereof.
' ' .
.' .
' ' ~3~3~
The present invention provides a method for treating aqueous systems to reduce or prevent the deposition of solid material therein comprising the addition to the water of an effective amount of at least one polymer or oopolymer formed from a monomer of the fol:Lowing general structure:
S ~1 ~
CH2=C-X-O-S-O M
o where RL is independentLy H or CH3; X ls (CH2)n with n an integer of 0 or 1 or -C~-O-CH2-CH-)nl nl is an integer of 1 to 10; and M is a metaL
o R
cation, ammonium or hydrogen. Comonomers useful with these polymerizable monomers include monocarboxylic acids or dicarboxylic acids and anhydrides thereof such as acrylic acid, methacrylic acid, maleic acid, itaconic acid or water soluble salts thereof, as well as acrylamide and its derivatives.
The addition of a third comonomer such as an ester of a ethylenically polymerizable mono-or dicar~oxylic acid, for example methyl acrylate, ethyl acrylate, methyl methacrylate, etc~i a maleate or fumarate ester or diester; a hydroxyalkylacrylate, for example hydroxyethyl acrylate, hydroxyethyl~,ethacryla~e, etc; allyl alcohol; vinyl esters such as vinyl acetate or vinyl propionate; vinyl alcohol obtained by hydrolyzing a vinyl ester based polymer; vinyl ethers; styrene; etc. has also been found beneficial.
In a preferred embodiment, the addition of polymers or copolymers of a 2-sulfato alkyl acrylate or methacrylate moncmer or water soluble salts ~- 25 thereof, more preferably of a 2-sulfato ethyl acrylate or methacrylate, .
~31~3~7 has been found most beneficial.
The above described polymers or copolymers have been found to have wide spread use as scale anti-deposition and dispersion agents, being effective in systems containing divalent salts of carb~nates, phosphates and sulfates~ etc., such as calcium carbonate and zinc phosphate, particularly in those systems containing iron ioxide. It is well known that industrial problems associated with scale formation can be com~ounded by the presence of soluble iron and su~spended matter. The ability of the polymers described herein to tolerate these interferences gives them a distinct advantage over other conventionally employed inhibitors.
The polymers used herein are those consisting essentially of 2 to 100 molar percent of a monomer of the following general structure:
R O
CH2=C-X-0-S-O M
where Rl is independently H or CH3; X is (CH2)n with n an integer of 0 or 1 or -C-(O-CH2-1 -)nl; nl is an integer of 1 to 10; and M is a metal - R
cation, ammonium or hydrogen; 0 to 98% of a o~monomer of acrylic acid, methacrylic acid, maleic acid or water soluble salts thereof or acrylamide and its derivatives; and 0 to 50% of a third monomer. Generally the molecular weights (Mw-weight average molecular weight as determined by gel permeation chromatography) of the copolymer will vary from 1000 to 100,000, preferably 1000 to 20,000 and most preferably from 1000 to 7500. Representative mono~ers useful herein include, for example, 2-sulfato ethyl a~rylate, ~ ~ulfato e~bl met~a rylate, 2-" 'fat propyl .:.' i ~3~3~7 acrylate, 2-sulfato propyl methacrylate, and water soluble salts thereof as well as of allyl sulfate and methallyl sulfate, and the water soluble salts thereof, etc.
The preferred class of 2-sulfato alkyl acrylate or methacrylate comoncmers utilized herein are characterized by the following formula:
R IR
CH2-1 COC-(CH2-CH-O-)n-SO3M wherein R is either hydrogen or methyl, R is either hydrogen or alkyl of from l to 22 carbon atoms, n is at least one positive integer of frcm 1 to 3 when Rl is either hydrogen or alkyl of fram 1 to 2 carbcn atoms, and n is one when Rl is an alkyl of frcm 3 to 22 carbon atoms. M is either hydrogen, ammonium or an alkali metal, e.g.
sodium, potassium or lithium, or an alkaline salt metal, e.g., calcium.
They are readily prepared by the reaction of a hydroxy alkyl acrylate or methacrylate with sulfamic acid in the presence of an organic amide catalyst using the procedure taught, for example, in U.S. Patent No.
3,839,393 issued Oct. 1, 1974 to Robert Steckler. Particularly preferred for use ln water treating, especially for aqueous systems containing very high phosphate levels, are the oopolymers containing ~t least 5~, preférably 10 to 50% by weight, of the 2-sulfato alkyl (meth)acrylate ccmoncmer.
The polymers utilized in accordance with the invention can be pre-pared by vinyl addition polymerization or by sulfation of a hydroxy funct-ional acrylic acid or salt pol~mer. More specifically, acrylic acid or derivatives thereof or their water soluble salts, e.g., sodiuml potassium, ammonium, etc. can be oopolymerized with the 2-sulfato alkyl (meth)-~ , ' ' ~3143~7 acrylate or other suitable moncmer for use herein under standard copoly-merization procedures utilizing free radical initiators such as benzoyl peroxide, azobisisobutyronitrile or redox initiators such as ferrous sulfate and ammonium persulfate. The molecular weights of the resulting copolymer can be controlled utilizing standard chain control agents such as secondary alcohols (isopropanol~, mercaptans, halocarbons etc.
The resulting polymers or copolymers are added to the aqueous systems in an`effective amount, i.e., an amount which will control the formation and deposition of scale and/or disperse the solid particulate materials.
These appropriate amounts are dependent upon the respective concentrations ; in the water of the potential scale and deposit formers, the pH of the water and the chemical and physical properties of the polymer. The criteria for proper treatment of any aqueous system would be apparent to those skilled in the art of water treatment. Generally amounts-of 1-50 parts per million have been found-most cost effective with the effective ~ -amount depending in large part, on the nature of the aqueous system being treated and the degree of build-up already in the system.
The polymers disclosed herein are generally used in oonjunction with one or more other water treating chemicals such as an inorganic phosphoric acid, phosphoric acid salt, organic phosphate or phosphonate acid ester or poly~alent metal salt. Generally, the phosphate or phosphonate ccmpounds are utilized in a range of about l to lO0 ppm (as PO4) and the polyvalent metal salts in an amount of l to 50 PF~ (as metal ion). The latter compounds may be added separately to the water being treated or may be canbined with an aqueous solution of the polymers of the invention and added continuously or intermittently to the water system. The polymers may also be used in conjuncticn with conventional corrosion inhibitors .
131~3~7 such as chr~nates, bichromates, tun~state, molybdates, nitrites, borates, silicates, oxycarboxy]ic acids, amino acids, catechols, aliphatic amino surface active agents, benzo triazole mercaptobenzothiazole, etc;
conventional scale and contamination inhibitors such as lignin derivatives, tannic acid, starch, polyacrylic acids, polyacrylic amide, etc; metal sequestering agents such as polyamines and polyamino carboxylic acids; as well as other conventional water treating agents.
While the preferred embodiments of the i~vention have been described, for example, in terms oE copol~nerization of a 2-sulfato alkyl acrylate with other comonomers, it will also be understood that similar results would be ohtained by use of a copolymer prepared by sulphating a copolymer containing hydroxy alkyl groups with the appropriate comonomers.
In the following examples, all parts are by weight and all temperatures in degrees Celsius unless otherwise noted. The test procedures utilized in evaluating the polymers of the invention are presented below.
Test ~rccedures~
In order to establish that the present invention provided overall effectiveness, two different evaluations were conducted which simulated water conditions found in oooling water systems where the concentration of calcium ions and phosphate ions are such as to provide a calcium phosphate scale-prone system. Ccmmercial grade polymers were also concurrently screened for comparative purposes.
:
_ 9 _ The evaluations were conducted utilizing solutions respectively containing calcium ion and ortho-phosphate ion. After mixing the two solutions and holding for the specified equilibration time, residual phosphate ion measurements were made after the mixture had been filtered.
High residual phosphate ion concentration indicated good inhibition.
The specifics of the test procedure are as follows:
Conditions Solutions Ca 2 = 250 ppn as CaO~3 (1) 36t76 g CaC12 2H20/li 10 PO4 3 = 6 ppm (2) 0.4482 g Na2HP04/liter deionized water T = 70C
pH = 8.5 17 Hour equilibration Procedure 1. Add 20 ml. of solution (1) to 1800 ml. deionized water in a 2 liter volumetric flask followed by 2 drops of concentrated hydrochloric acid. -2~ Add 40 ml. of solution (2) and-bring volume to,:2-,liters with dis~illed ' 20 water.
; 3. Place 100 ~1. aliquots of solution ln clean 4 oz. glass bottles.
4. Add desired treatment~
5. Adjust pH to 8.5 with sodium hydroxide and place in 70C water bath.
6. Allow samples to equilibrate for 17 hours.
7. Remove sam~les from water bath and filter ~,mediately through 0.22 micron filters; allow samples to cool.
. Preparation for analysis:
a. 5 mls. filtrate b. Dilute to 10 ml. in 25 ml. volumetric flask.
c. Add 5 ml~ colormetric reagent made previously by dissolving 10 9. of ascorbic acid into 100 ml. of equal volumes of 2.5 ammonium molybdate and 1% bismuth subcarbonate.
d. Dilute to volume and allow to stand 5 minutes for color development.
9. Take absorbance measurements using Bausch and Lomb Spectronic 20 photom~ter (660 nm).
,. . , , ; .
-.. . .
~3:~3~7 10. Usi~ current calibration curve (Absorbance vs. ppm PO4 3) find ppm PO4 of each sample.
Calculation:
~ Inhibition = ppm PO4 (treated)-ppm PO4 (blank) ~` ppm PO4 3(stock)-ppm PO4 3 (blank) In a second series of tests, the procedure described above was repeated but the aqueous systems were modified so as to additionally contain 2 parts per million ferric ion.
Calcium sulfate and calcium carbonate inhibition were tested using NACE (National Association of Corrosion Engineers) Standard TM-03-74 developed by Tack Group T-lD-9 of Unit Committee T-l on Control of Oil ; Field Corrosion by Chemical TreatmentO
EXAMPLE
A 50:50 weight percent ccmposition of acrylic acid: 2-sulfato ethyl methacrylate, was prepared using the following procedure:
Deionised water (200 gms) and isopropanol (200 gms) were charged to ~ the reaction vessel and heated to reflux. A monomer solution of acrylic :~.
acid (200 gms) and the a~moniu~ salt of hydroxy ethyl methacrylate sulphate (800 gms of 25.0~ actives solution) and a catalyst solution of sodium persulphate (16.0 gms) in deionized water (100 gms) were added over three hours to the refluxing medium.
The reaction was held at reflux for one hour longer. An isopropanol/water azeotrope (440 gms) was removed under vacuum. The solution was cooled and sodium hydroxide (115 gms) in deionized water (125 gms) was added with cooling to yield 1317 gms of 35.0% w/w polymer solution.
~31~3~
The product was characterized using Gel Permeation Chromatography and gave a molecular weight parameter of Mw--5000; Mn=2200 with respect to scdium polyacrylate standards. (Mw is the weight average molecular weight and Mn is the number average molecular weight).
Using a similar procedure, varying the amounts of the mon~neric ccmponents, ~ther copolymers as described below were prepared. In the tables, the following abbreviations are used:
; AA = acrylic acid HPA = hydroxypropyl acrylate Allyl OH = allyl alcohol SSMA = sulfonated polystyrene maleic anhydride HE~I~ = hydroxy ethyl methacrylate HEMAS = 2-sulfato ethyl methacrylate ammonium salt Polymer C~nposj~ e~e~s=) M5900) M2n500 56 AA: 34 HPA: 10 HEMAS 3500 1500 56 AA: 34 HPA: 10 HEMA 4700 2200 60 AA: 40 HEMAS 4650 1900 50 AA: 50 HEMAS ~ -~ 5000 2200 50 AA: 50 HEMA ;~ ~- - ~ 6800 2200 25 AA: 75 H~MAS ~ 5600 2260 --62.5 AA: 37.5 HPA ~~ ~ 3700 1500 ~ :
Polyacrylic acid 3500 1800 Polyphosphino carboxylic acid 3400 1300 (1) Wt. average Molecular Weight ~2) Number average Molecular Weight The polymers described above were evaluated usin~ the procedures described previously. Additionally, svaluations were carried out on several cQmmsrcially available water treab~ent polymers as well as on polymers prepared utilizing the unsulfonated hydroxy ethyl methacrylate All polymers were tested at a calculated dose in the sodium salt form.
The results of the testing are shown in Tables I-IV below.
- , ` ::.
.; "' " ` ' ' ' '~
. .
, , ~ ,- , : , :, ' ~
The present invention relates to a method for controlling the formation and deposition of scale forming salts in aqueous media. The polymers diselosed herein also find use as part of a corrosion control system to maintain solubilization of the corrosion inhibitors such as zinc and phosphate compounds.
Deposits in cooling waters are classified into two categories -foulants and scales. Foulants usually result from suspended solids in the system and are high in organics. Scales on the other hand are hard, adherent mineral deposits that precipitate from solution. Foulants can usually be removed by pre-treatment of the cooling water, sueh as by filtration. It is the prevention of deposition of scale with which the present invention is primarily concerned.
The problems associated with mineral sealing in cooling water systems have been known for many years. In such syste~s water flowing around heat exchange equipment deposlts mineral scale on the surface of the installation. This scale builds up in layers giving an insulation effect, reducing the heat transfer of the apparatus and also resulting in poor water cireulation. Eventually this neeessitates the shut-down of the unit b~ allow me hanical or ch mical cleaning.
., . ; ~ '' ' ~ ' ,' , .
~ 3 ~
Depositions in lines, heat exchange equipment, etc., may originate from several causes. For example, the precipitation of calcium carbonate and calcium phosphate will form scale, but prcducts of corrosion also result in a deposit of iron oxide salts. These are deposited as scales due to changes in temperature, pH, concentration, pressure and ; inccmpatible water additives.
The development of high pH and/or non-chromate corrosion programs has increased the potential for scale formation due to chemical precipitation.
In particular, since most of the treatments currently used include phosphate and¦or phosphonic acid compounds, the reversion of the polyphosphates and the organic p~losphates plus the use of high alkaline operating conditions leads to the formation and deposition of highly insoluble calcium phosphate.
Although steam generating systems are different from cooling-water ~ - ~
systems, they share common problems relating to calcium phosphate and iro~n - --oxide formation and other mineral scale deposition~ In this regard, the ~ formation of scale and sludge deposits on boiler heating surfaces is the - most serious water problem encountered in steam generation. Although current industrial steam producing systems make use of external treatments of the boiler feed water to reduce scale forming ions, those operations are not totally effective and do not provide adequate treatment sinoe muds, sludge, silts and hardness-imparting ions are not treated thereby, and eventually are introduced into the steam generating system.
Accordingly, internal treatment, i.e., the use of solubilizing chemicals which have the ability to keep the scale-forming materials in solution at concentrations substantially higher than would be expected are used throughout the industry in an attempt to alleviate the problems - ~31~357 encountered by such scale deposit1on. Such solubilizing chemicals include alginates, lignins, lignosulfonates, tannins, carboxymethyl cellulose materials, and synthetic polymers such as polyacrylates and polymethacrylates. Since most of the solubilizing chemicals used are effective for only one or two of the scale forming salts, it is necessary to usc a mixture of chemicals in order to pro~ide adequate scale prevention in these aqueous systems. Thus, depending upon the chemicals present, it may be necessary to employ polymer dispersants to control calcium sulfate and calcium phosphate with organo-phosphorous chemicals used to disperse calcium carbonate. Further, the presence of iron oxide or other materials may additionally reduce the action of the scale prevention chemicals being utilized.
Plthough the foregoing is directed for the most part to cooling water systems and steam generating systems, the same problems occur in scrubber systems and the like. Any aqueous system having calcium and magnesium cations and the exemplified anions, in particular phosphate, will experience the for~.atlon and deposition of the scaling salts.
A further need for water treatment polymers such as are disclosed herein arises in the case of corrosion control systems where there has been an increasing enphasis on the use of high pH and/or non-chrcmate agents such as those utilizing phosphate and/or zinc. These latter materials have~limited solubility and it has been found necessary to add other chemicals to the systems in order to maintain the solubility thereof.
' ' .
.' .
' ' ~3~3~
The present invention provides a method for treating aqueous systems to reduce or prevent the deposition of solid material therein comprising the addition to the water of an effective amount of at least one polymer or oopolymer formed from a monomer of the fol:Lowing general structure:
S ~1 ~
CH2=C-X-O-S-O M
o where RL is independentLy H or CH3; X ls (CH2)n with n an integer of 0 or 1 or -C~-O-CH2-CH-)nl nl is an integer of 1 to 10; and M is a metaL
o R
cation, ammonium or hydrogen. Comonomers useful with these polymerizable monomers include monocarboxylic acids or dicarboxylic acids and anhydrides thereof such as acrylic acid, methacrylic acid, maleic acid, itaconic acid or water soluble salts thereof, as well as acrylamide and its derivatives.
The addition of a third comonomer such as an ester of a ethylenically polymerizable mono-or dicar~oxylic acid, for example methyl acrylate, ethyl acrylate, methyl methacrylate, etc~i a maleate or fumarate ester or diester; a hydroxyalkylacrylate, for example hydroxyethyl acrylate, hydroxyethyl~,ethacryla~e, etc; allyl alcohol; vinyl esters such as vinyl acetate or vinyl propionate; vinyl alcohol obtained by hydrolyzing a vinyl ester based polymer; vinyl ethers; styrene; etc. has also been found beneficial.
In a preferred embodiment, the addition of polymers or copolymers of a 2-sulfato alkyl acrylate or methacrylate moncmer or water soluble salts ~- 25 thereof, more preferably of a 2-sulfato ethyl acrylate or methacrylate, .
~31~3~7 has been found most beneficial.
The above described polymers or copolymers have been found to have wide spread use as scale anti-deposition and dispersion agents, being effective in systems containing divalent salts of carb~nates, phosphates and sulfates~ etc., such as calcium carbonate and zinc phosphate, particularly in those systems containing iron ioxide. It is well known that industrial problems associated with scale formation can be com~ounded by the presence of soluble iron and su~spended matter. The ability of the polymers described herein to tolerate these interferences gives them a distinct advantage over other conventionally employed inhibitors.
The polymers used herein are those consisting essentially of 2 to 100 molar percent of a monomer of the following general structure:
R O
CH2=C-X-0-S-O M
where Rl is independently H or CH3; X is (CH2)n with n an integer of 0 or 1 or -C-(O-CH2-1 -)nl; nl is an integer of 1 to 10; and M is a metal - R
cation, ammonium or hydrogen; 0 to 98% of a o~monomer of acrylic acid, methacrylic acid, maleic acid or water soluble salts thereof or acrylamide and its derivatives; and 0 to 50% of a third monomer. Generally the molecular weights (Mw-weight average molecular weight as determined by gel permeation chromatography) of the copolymer will vary from 1000 to 100,000, preferably 1000 to 20,000 and most preferably from 1000 to 7500. Representative mono~ers useful herein include, for example, 2-sulfato ethyl a~rylate, ~ ~ulfato e~bl met~a rylate, 2-" 'fat propyl .:.' i ~3~3~7 acrylate, 2-sulfato propyl methacrylate, and water soluble salts thereof as well as of allyl sulfate and methallyl sulfate, and the water soluble salts thereof, etc.
The preferred class of 2-sulfato alkyl acrylate or methacrylate comoncmers utilized herein are characterized by the following formula:
R IR
CH2-1 COC-(CH2-CH-O-)n-SO3M wherein R is either hydrogen or methyl, R is either hydrogen or alkyl of from l to 22 carbon atoms, n is at least one positive integer of frcm 1 to 3 when Rl is either hydrogen or alkyl of fram 1 to 2 carbcn atoms, and n is one when Rl is an alkyl of frcm 3 to 22 carbon atoms. M is either hydrogen, ammonium or an alkali metal, e.g.
sodium, potassium or lithium, or an alkaline salt metal, e.g., calcium.
They are readily prepared by the reaction of a hydroxy alkyl acrylate or methacrylate with sulfamic acid in the presence of an organic amide catalyst using the procedure taught, for example, in U.S. Patent No.
3,839,393 issued Oct. 1, 1974 to Robert Steckler. Particularly preferred for use ln water treating, especially for aqueous systems containing very high phosphate levels, are the oopolymers containing ~t least 5~, preférably 10 to 50% by weight, of the 2-sulfato alkyl (meth)acrylate ccmoncmer.
The polymers utilized in accordance with the invention can be pre-pared by vinyl addition polymerization or by sulfation of a hydroxy funct-ional acrylic acid or salt pol~mer. More specifically, acrylic acid or derivatives thereof or their water soluble salts, e.g., sodiuml potassium, ammonium, etc. can be oopolymerized with the 2-sulfato alkyl (meth)-~ , ' ' ~3143~7 acrylate or other suitable moncmer for use herein under standard copoly-merization procedures utilizing free radical initiators such as benzoyl peroxide, azobisisobutyronitrile or redox initiators such as ferrous sulfate and ammonium persulfate. The molecular weights of the resulting copolymer can be controlled utilizing standard chain control agents such as secondary alcohols (isopropanol~, mercaptans, halocarbons etc.
The resulting polymers or copolymers are added to the aqueous systems in an`effective amount, i.e., an amount which will control the formation and deposition of scale and/or disperse the solid particulate materials.
These appropriate amounts are dependent upon the respective concentrations ; in the water of the potential scale and deposit formers, the pH of the water and the chemical and physical properties of the polymer. The criteria for proper treatment of any aqueous system would be apparent to those skilled in the art of water treatment. Generally amounts-of 1-50 parts per million have been found-most cost effective with the effective ~ -amount depending in large part, on the nature of the aqueous system being treated and the degree of build-up already in the system.
The polymers disclosed herein are generally used in oonjunction with one or more other water treating chemicals such as an inorganic phosphoric acid, phosphoric acid salt, organic phosphate or phosphonate acid ester or poly~alent metal salt. Generally, the phosphate or phosphonate ccmpounds are utilized in a range of about l to lO0 ppm (as PO4) and the polyvalent metal salts in an amount of l to 50 PF~ (as metal ion). The latter compounds may be added separately to the water being treated or may be canbined with an aqueous solution of the polymers of the invention and added continuously or intermittently to the water system. The polymers may also be used in conjuncticn with conventional corrosion inhibitors .
131~3~7 such as chr~nates, bichromates, tun~state, molybdates, nitrites, borates, silicates, oxycarboxy]ic acids, amino acids, catechols, aliphatic amino surface active agents, benzo triazole mercaptobenzothiazole, etc;
conventional scale and contamination inhibitors such as lignin derivatives, tannic acid, starch, polyacrylic acids, polyacrylic amide, etc; metal sequestering agents such as polyamines and polyamino carboxylic acids; as well as other conventional water treating agents.
While the preferred embodiments of the i~vention have been described, for example, in terms oE copol~nerization of a 2-sulfato alkyl acrylate with other comonomers, it will also be understood that similar results would be ohtained by use of a copolymer prepared by sulphating a copolymer containing hydroxy alkyl groups with the appropriate comonomers.
In the following examples, all parts are by weight and all temperatures in degrees Celsius unless otherwise noted. The test procedures utilized in evaluating the polymers of the invention are presented below.
Test ~rccedures~
In order to establish that the present invention provided overall effectiveness, two different evaluations were conducted which simulated water conditions found in oooling water systems where the concentration of calcium ions and phosphate ions are such as to provide a calcium phosphate scale-prone system. Ccmmercial grade polymers were also concurrently screened for comparative purposes.
:
_ 9 _ The evaluations were conducted utilizing solutions respectively containing calcium ion and ortho-phosphate ion. After mixing the two solutions and holding for the specified equilibration time, residual phosphate ion measurements were made after the mixture had been filtered.
High residual phosphate ion concentration indicated good inhibition.
The specifics of the test procedure are as follows:
Conditions Solutions Ca 2 = 250 ppn as CaO~3 (1) 36t76 g CaC12 2H20/li 10 PO4 3 = 6 ppm (2) 0.4482 g Na2HP04/liter deionized water T = 70C
pH = 8.5 17 Hour equilibration Procedure 1. Add 20 ml. of solution (1) to 1800 ml. deionized water in a 2 liter volumetric flask followed by 2 drops of concentrated hydrochloric acid. -2~ Add 40 ml. of solution (2) and-bring volume to,:2-,liters with dis~illed ' 20 water.
; 3. Place 100 ~1. aliquots of solution ln clean 4 oz. glass bottles.
4. Add desired treatment~
5. Adjust pH to 8.5 with sodium hydroxide and place in 70C water bath.
6. Allow samples to equilibrate for 17 hours.
7. Remove sam~les from water bath and filter ~,mediately through 0.22 micron filters; allow samples to cool.
. Preparation for analysis:
a. 5 mls. filtrate b. Dilute to 10 ml. in 25 ml. volumetric flask.
c. Add 5 ml~ colormetric reagent made previously by dissolving 10 9. of ascorbic acid into 100 ml. of equal volumes of 2.5 ammonium molybdate and 1% bismuth subcarbonate.
d. Dilute to volume and allow to stand 5 minutes for color development.
9. Take absorbance measurements using Bausch and Lomb Spectronic 20 photom~ter (660 nm).
,. . , , ; .
-.. . .
~3:~3~7 10. Usi~ current calibration curve (Absorbance vs. ppm PO4 3) find ppm PO4 of each sample.
Calculation:
~ Inhibition = ppm PO4 (treated)-ppm PO4 (blank) ~` ppm PO4 3(stock)-ppm PO4 3 (blank) In a second series of tests, the procedure described above was repeated but the aqueous systems were modified so as to additionally contain 2 parts per million ferric ion.
Calcium sulfate and calcium carbonate inhibition were tested using NACE (National Association of Corrosion Engineers) Standard TM-03-74 developed by Tack Group T-lD-9 of Unit Committee T-l on Control of Oil ; Field Corrosion by Chemical TreatmentO
EXAMPLE
A 50:50 weight percent ccmposition of acrylic acid: 2-sulfato ethyl methacrylate, was prepared using the following procedure:
Deionised water (200 gms) and isopropanol (200 gms) were charged to ~ the reaction vessel and heated to reflux. A monomer solution of acrylic :~.
acid (200 gms) and the a~moniu~ salt of hydroxy ethyl methacrylate sulphate (800 gms of 25.0~ actives solution) and a catalyst solution of sodium persulphate (16.0 gms) in deionized water (100 gms) were added over three hours to the refluxing medium.
The reaction was held at reflux for one hour longer. An isopropanol/water azeotrope (440 gms) was removed under vacuum. The solution was cooled and sodium hydroxide (115 gms) in deionized water (125 gms) was added with cooling to yield 1317 gms of 35.0% w/w polymer solution.
~31~3~
The product was characterized using Gel Permeation Chromatography and gave a molecular weight parameter of Mw--5000; Mn=2200 with respect to scdium polyacrylate standards. (Mw is the weight average molecular weight and Mn is the number average molecular weight).
Using a similar procedure, varying the amounts of the mon~neric ccmponents, ~ther copolymers as described below were prepared. In the tables, the following abbreviations are used:
; AA = acrylic acid HPA = hydroxypropyl acrylate Allyl OH = allyl alcohol SSMA = sulfonated polystyrene maleic anhydride HE~I~ = hydroxy ethyl methacrylate HEMAS = 2-sulfato ethyl methacrylate ammonium salt Polymer C~nposj~ e~e~s=) M5900) M2n500 56 AA: 34 HPA: 10 HEMAS 3500 1500 56 AA: 34 HPA: 10 HEMA 4700 2200 60 AA: 40 HEMAS 4650 1900 50 AA: 50 HEMAS ~ -~ 5000 2200 50 AA: 50 HEMA ;~ ~- - ~ 6800 2200 25 AA: 75 H~MAS ~ 5600 2260 --62.5 AA: 37.5 HPA ~~ ~ 3700 1500 ~ :
Polyacrylic acid 3500 1800 Polyphosphino carboxylic acid 3400 1300 (1) Wt. average Molecular Weight ~2) Number average Molecular Weight The polymers described above were evaluated usin~ the procedures described previously. Additionally, svaluations were carried out on several cQmmsrcially available water treab~ent polymers as well as on polymers prepared utilizing the unsulfonated hydroxy ethyl methacrylate All polymers were tested at a calculated dose in the sodium salt form.
The results of the testing are shown in Tables I-IV below.
- , ` ::.
.; "' " ` ' ' ' '~
. .
, , ~ ,- , : , :, ' ~
3 ~ 7 TABLE I
g _HIBITION OF CALCIUM PHOSPHATE (No Iron~
Polymer/Dosage _ 2.5 rF~ 5~}~
71 AA~ 19 Allyl OH: 10 HEMAS 14 73 96 56 AA: 34 HPA: 10 HEMAS 17 96 97 56 AA 34 HPA: 10 HEMA - - 85 50 A~: 50 HEMAS 20 50 100 50 AA: 50 HEMA - - 85 62.5 AA: 37.5 ~A - 77 91 65:35 SSMA - 56 94 Polyacrylic acid - ~ O
Polyphosphin~ carboxylic acid - - 82 : TABLE II
% INHJBITION _F C~LCIUM PHOSPHATE (2 p ~
15 Prcduct/Dosa~e S ppm10 ppm .
71 AA: 19 Allyl OH: 10 HEMAS 44 78 ~: 56 AA: 34 HPA: 10 HEMAS 45 95 ` 56 AA: 34 HPA: 10 HEMA - 80 : 50 AA: 50 HEMAS - 90 50 AA: 50 HEMA - 82 62.5 AA: 37.5 HPA - 87 85:15 SSMA - 45 65:35 SSMA 36 87 Polyphosphino carboxylic acid - 58 - . _, _ , ,; .
, ~ . , - 13 - ~3~3~i7 TABLE III
~ .
~ Polymer ~ 5 ee~ J~e~
71 AA: 19 Allyl OH: 10 HEMAS 36 39 62.5 AA: 37.5 HPA 31 46 85:15 SSMA 0 65: 35 SSMA 0 31 Polyacrylic acid 66 95 TABLE IV
% INHIBITION OF CAI CII~M SULFATE
Pol~ner/Dosage _ _ _ 0.5 ppm _2.5 p~_5 p~n 71 AAo l9 Allyl OH 10 HEMAS - 51 88 ~.
56 AA: 34 HPA: 10 HEMP~S - : . ~s9 84 , 62.5 AA: 37.5 HPA -- 98 100 5:15 SSMA 13 67 96 65:35 SSMA -- 96 100 Polyacrylic acid 96 100 __ _ _ _ .
~ The results of Tables I and II show that the copolymers o~ the : 20 invention are very effective as calcium phosp.hate inhibitors at treatment rates as low as 5 ppm. Additionally, at a 10 pp~ treatment rate with 2 ppm iron present, the AA:I~A/HE~AS copolymer inhibited 95~6 of the phosphate. In the calcium carbonate and calcium sulfate testing, the :, .
..
. , . . , .
. :
'" " ~ .
- 13~3~
copolymers of the inven~ion did not function as efficiently as the low molecular weight polyacrylic acid but their performance was better than many of the otller commercially employed copolymers.
The test procedure described above was repeated using a variety of ratios and camponents in the copolymer. In this series of tests, antimony potassium tartarate solution was used in the single reaction reagent and a wavelength setting of 880 nm was employed. Results are shown in Table V.
TABLE V
CALCIUkl PHOSPHAli3 INHIBITION BY HEMA SULE`ATE COPOLYI`IERS
Percentage Inhibition Pol ers/Dosa e S ppm 7 ppm 10 ppm vm , ~ -71 AA: 19 Allyl OH: 10 HBMAS 10 95 100 56 AA: 34 HPA: 10 HEMAS50 100 100 15 60 AA: 40 HEMAS 35 95 95 ; 50 AA: 50 HEMAS 75 80 90 25 AA: 75 HEMAS 75 85 85 62.5 ~A: 37.5 ED?A 80 100 100 Polyacrylic acid 0 0 0 The follcw1ng tests were performed in order to evaluate the behavior -~ of the water treatment polymers in aqueous media containg hiyher levels of phosphate since recent observations have indicated that higher levels of phosphate and calcium are now encountered in the field.
' ~ . ~
13143~7 ; The procedures described previously were repeated usiny 10 ppm phosphate and 300 ppm calcium ions at a pH of 8.5, 70C for 16 hours with and without 2 ppm iron with a dosage level of 15 ppm as sodi~ salt. The results are shown in Table YI.
TABLE Vl Percentage Inhibition Polymer No IronWith Iron 56 AA: 34 HPA: 10 HEMPS90 75 56 AA: 34 HPA: 10 HEMA 55 35 10 50 AA: 50 HEMAS 100 75 50 AA: 50 HEMA 65 35 65:35 SSMA 80 40 Polyphosphino carboxylic acid 10 --_ _ :~ .
~ ~ The results show that the polymers-of the present invention ;-~
contalning at least 10% by weight HEMAS show significant improvement in performance over those o the prior art in these higher phosphate systems.
~` EXA~PLE 4 This test was performed in order to show the performance of the water . ~
treatment polymers in aqueous systems which may be exposed to high .~
temperatures. In this example, the evaluations were performed as in Example 2 but using a ter~erature of 90C and a dosage o 20 ppm as sodium salt. m e results are shown in Table VII.
.
' .
,' , .
~3~357 TABLE VII
Percentage Inhibition With 23pp~ With ~ ppm 56 AA: 34 HPA: 10 HEMAS 0 0 0 56 AA: 34 HPA: 10 HEMA 0 0 0 SO AA: 50 HEMAS 80 75 65 ; 50 AA: 50 HEMA 65 58 55 62 . 5 AA: 37. 5 HPA . 0 10 In conclusion, the results of the examples presented herein show that the performance of the copolymers of the invention as a primary phosphate inhibitor and as a primary calcium phosphate inhibitor as ccmpared to other cc~mercially available products were excellent. In addition, their performance in the presence of iron in the phosphate test and moderate 15 tolerance to other calcium salts contribute to their uniqueness for treatment of scale control in aqueous systems. As such, they are applicable to any aqueous system where calcium phosphate formation and precipitation is a potential problem.
When tested for their ability to disperse suspended matter such as 20 china clay, the pol~mers of the invention, particularly the 2-sulfato alkyltmeth)acrylates, were found to p~ssess adequate dispersant activity but were not as efficient as sodium polyacrylate homopolymers.
Similar results would be obtained utilizing other co~olymers discussed herein including, for e~ample, copolymer~ of 2-sulfato e~hyl methacrylate, 2-sulfato propyl acrylate, 2-sulfato propyl methacrylate, allyl sulfate, methallyl sulfate, etc.
'~
.
'
g _HIBITION OF CALCIUM PHOSPHATE (No Iron~
Polymer/Dosage _ 2.5 rF~ 5~}~
71 AA~ 19 Allyl OH: 10 HEMAS 14 73 96 56 AA: 34 HPA: 10 HEMAS 17 96 97 56 AA 34 HPA: 10 HEMA - - 85 50 A~: 50 HEMAS 20 50 100 50 AA: 50 HEMA - - 85 62.5 AA: 37.5 ~A - 77 91 65:35 SSMA - 56 94 Polyacrylic acid - ~ O
Polyphosphin~ carboxylic acid - - 82 : TABLE II
% INHJBITION _F C~LCIUM PHOSPHATE (2 p ~
15 Prcduct/Dosa~e S ppm10 ppm .
71 AA: 19 Allyl OH: 10 HEMAS 44 78 ~: 56 AA: 34 HPA: 10 HEMAS 45 95 ` 56 AA: 34 HPA: 10 HEMA - 80 : 50 AA: 50 HEMAS - 90 50 AA: 50 HEMA - 82 62.5 AA: 37.5 HPA - 87 85:15 SSMA - 45 65:35 SSMA 36 87 Polyphosphino carboxylic acid - 58 - . _, _ , ,; .
, ~ . , - 13 - ~3~3~i7 TABLE III
~ .
~ Polymer ~ 5 ee~ J~e~
71 AA: 19 Allyl OH: 10 HEMAS 36 39 62.5 AA: 37.5 HPA 31 46 85:15 SSMA 0 65: 35 SSMA 0 31 Polyacrylic acid 66 95 TABLE IV
% INHIBITION OF CAI CII~M SULFATE
Pol~ner/Dosage _ _ _ 0.5 ppm _2.5 p~_5 p~n 71 AAo l9 Allyl OH 10 HEMAS - 51 88 ~.
56 AA: 34 HPA: 10 HEMP~S - : . ~s9 84 , 62.5 AA: 37.5 HPA -- 98 100 5:15 SSMA 13 67 96 65:35 SSMA -- 96 100 Polyacrylic acid 96 100 __ _ _ _ .
~ The results of Tables I and II show that the copolymers o~ the : 20 invention are very effective as calcium phosp.hate inhibitors at treatment rates as low as 5 ppm. Additionally, at a 10 pp~ treatment rate with 2 ppm iron present, the AA:I~A/HE~AS copolymer inhibited 95~6 of the phosphate. In the calcium carbonate and calcium sulfate testing, the :, .
..
. , . . , .
. :
'" " ~ .
- 13~3~
copolymers of the inven~ion did not function as efficiently as the low molecular weight polyacrylic acid but their performance was better than many of the otller commercially employed copolymers.
The test procedure described above was repeated using a variety of ratios and camponents in the copolymer. In this series of tests, antimony potassium tartarate solution was used in the single reaction reagent and a wavelength setting of 880 nm was employed. Results are shown in Table V.
TABLE V
CALCIUkl PHOSPHAli3 INHIBITION BY HEMA SULE`ATE COPOLYI`IERS
Percentage Inhibition Pol ers/Dosa e S ppm 7 ppm 10 ppm vm , ~ -71 AA: 19 Allyl OH: 10 HBMAS 10 95 100 56 AA: 34 HPA: 10 HEMAS50 100 100 15 60 AA: 40 HEMAS 35 95 95 ; 50 AA: 50 HEMAS 75 80 90 25 AA: 75 HEMAS 75 85 85 62.5 ~A: 37.5 ED?A 80 100 100 Polyacrylic acid 0 0 0 The follcw1ng tests were performed in order to evaluate the behavior -~ of the water treatment polymers in aqueous media containg hiyher levels of phosphate since recent observations have indicated that higher levels of phosphate and calcium are now encountered in the field.
' ~ . ~
13143~7 ; The procedures described previously were repeated usiny 10 ppm phosphate and 300 ppm calcium ions at a pH of 8.5, 70C for 16 hours with and without 2 ppm iron with a dosage level of 15 ppm as sodi~ salt. The results are shown in Table YI.
TABLE Vl Percentage Inhibition Polymer No IronWith Iron 56 AA: 34 HPA: 10 HEMPS90 75 56 AA: 34 HPA: 10 HEMA 55 35 10 50 AA: 50 HEMAS 100 75 50 AA: 50 HEMA 65 35 65:35 SSMA 80 40 Polyphosphino carboxylic acid 10 --_ _ :~ .
~ ~ The results show that the polymers-of the present invention ;-~
contalning at least 10% by weight HEMAS show significant improvement in performance over those o the prior art in these higher phosphate systems.
~` EXA~PLE 4 This test was performed in order to show the performance of the water . ~
treatment polymers in aqueous systems which may be exposed to high .~
temperatures. In this example, the evaluations were performed as in Example 2 but using a ter~erature of 90C and a dosage o 20 ppm as sodium salt. m e results are shown in Table VII.
.
' .
,' , .
~3~357 TABLE VII
Percentage Inhibition With 23pp~ With ~ ppm 56 AA: 34 HPA: 10 HEMAS 0 0 0 56 AA: 34 HPA: 10 HEMA 0 0 0 SO AA: 50 HEMAS 80 75 65 ; 50 AA: 50 HEMA 65 58 55 62 . 5 AA: 37. 5 HPA . 0 10 In conclusion, the results of the examples presented herein show that the performance of the copolymers of the invention as a primary phosphate inhibitor and as a primary calcium phosphate inhibitor as ccmpared to other cc~mercially available products were excellent. In addition, their performance in the presence of iron in the phosphate test and moderate 15 tolerance to other calcium salts contribute to their uniqueness for treatment of scale control in aqueous systems. As such, they are applicable to any aqueous system where calcium phosphate formation and precipitation is a potential problem.
When tested for their ability to disperse suspended matter such as 20 china clay, the pol~mers of the invention, particularly the 2-sulfato alkyltmeth)acrylates, were found to p~ssess adequate dispersant activity but were not as efficient as sodium polyacrylate homopolymers.
Similar results would be obtained utilizing other co~olymers discussed herein including, for e~ample, copolymer~ of 2-sulfato e~hyl methacrylate, 2-sulfato propyl acrylate, 2-sulfato propyl methacrylate, allyl sulfate, methallyl sulfate, etc.
'~
.
'
Claims (10)
1. A method for treating aqueous systems to reduce or prevent the deposition of solid material therein comprising the addition thereto of an effective amount of a polymer or copolymer consisting essentially of 2 to 100 mole percent of a monomer of the following general structure:
where R1 is independently H or CH3; X is (CH2)n with n an integer of 0 to 1 or ; n1 is an integer of 1 to 10; and M is a metal cation, ammonium or hydrogen; 0 to 98%-of a comonomer selected from the-group consisting of acrylic acid, methacrylic acid, maleic acid and water soluble salt, thereof, acrylamide and its derivatives thereof; and 0 to 50% of a third copolymerizable comonomer.
where R1 is independently H or CH3; X is (CH2)n with n an integer of 0 to 1 or ; n1 is an integer of 1 to 10; and M is a metal cation, ammonium or hydrogen; 0 to 98%-of a comonomer selected from the-group consisting of acrylic acid, methacrylic acid, maleic acid and water soluble salt, thereof, acrylamide and its derivatives thereof; and 0 to 50% of a third copolymerizable comonomer.
2. A method for treating aqueous systems to reduce or prevent the deposition of solid material therein comprising the addition thereto of an effective amount of a polymer or copolymer consisting essentially of 2 to 100 mole percent of a 2-sulfato alkyl acrylate or methacrylate or a water soluble salt thereof; 0 to 98% of a comonomer selected from the group consisting of acrylic acid, methacrylic acid, maleic acid and water soluble salt, thereof, acrylamide and its derivatives thereof; and 0 to 50% of a third copolymerizable comonomer.
3. The method of Claim 1 or 2 wherein the polymer or copolymer has a molecular weight of 1000 to 100,000.
4. The method of Claim 3 wherein the polymer or copolymer has a molecular weight of 1000 to 7500.
5. The method of Claim 1 or 2 wherein the third comonomer is selected from the group consisting of esters of ethylenically polymerizable carboxylic acids, maleate and fumarate esters and diesters, hydroxyalkyl acrylates, allyl alcohol, vinyl esters, vinyl alcohol obtained by hydrolyzing a vinyl ester based polymer, vinyl ethers and styrene.
6. The method of Claim 1 wherein the aqueous system is a steam generating system, a cooling water system or a gas scrubbing system.
7. The method of Claim 1 or 2 wherein the 2-sulfato alkyl methacrylate is 2-sulfato ethyl methacrylate or a water soluble salt thereof and it is present in an amount of at least 5 molar percent.
8. The method of Claim 1 or 2 wherein the copolymer consists essentially of acrylic acid, allyl alcohol and 2-sulfato ethyl methacrylate ammonium salt; acrylic acid, hydroxypropyl acrylate and 2-sulfato ethyl methacrylate, or acrylic acid and 2-sulfato ethyl methacrylate ammonium salt.
9. A copolymer composition suitable for use in aqueous media consisting essentially of 2 to 90 mole percent of a monomer of the following general structure:
where R1 is independently H or CH3; X is (CH2)n with n an integer of 0 or 1 or ; n1 is an integer of 1 to 10; and M is a metal cation, ammonium or hydrogen 10 to 98% of a comonomer selected from the group consisting of acrylic acid, methacrylic acid, maleic acid and water soluble salts thereof, acrylamide and derivatives thereof; and 0 to 50% of a third copolymerizable comonomer selected from the group consisting of esters of ethylenically polymerizable carboxylic acids, maleate and fumarate esters and diesters, hydroxyalkyl acrylates, allyl alcohol, vinyl esters, vinyl alcohol obtained by hydrolyzing a vinyl ester based polymer, vinyl ethers and styrene.
where R1 is independently H or CH3; X is (CH2)n with n an integer of 0 or 1 or ; n1 is an integer of 1 to 10; and M is a metal cation, ammonium or hydrogen 10 to 98% of a comonomer selected from the group consisting of acrylic acid, methacrylic acid, maleic acid and water soluble salts thereof, acrylamide and derivatives thereof; and 0 to 50% of a third copolymerizable comonomer selected from the group consisting of esters of ethylenically polymerizable carboxylic acids, maleate and fumarate esters and diesters, hydroxyalkyl acrylates, allyl alcohol, vinyl esters, vinyl alcohol obtained by hydrolyzing a vinyl ester based polymer, vinyl ethers and styrene.
10. A copolymer composition suitable for use in aqueous media consisting essentially of 2 to 90 mole percent of a 2-sulfato alkyl acrylate or methacrylate; 10 to 98% of a comonomer selected from the group consisting of acrylic acid, methacrylic acid, maleic acid and water soluble salts thereof, acrylamide and derivatives thereof; and 0 to 50% of a third copolymerizable comonomer.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US004,395 | 1987-01-16 | ||
| US07/004,395 US4836933A (en) | 1987-01-16 | 1987-01-16 | Water treatment polymer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1314357C true CA1314357C (en) | 1993-03-09 |
Family
ID=21710593
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000556224A Expired - Fee Related CA1314357C (en) | 1987-01-16 | 1988-01-11 | Water treatment polymer |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US4836933A (en) |
| EP (1) | EP0274733B1 (en) |
| JP (1) | JPS63175698A (en) |
| CA (1) | CA1314357C (en) |
| DE (1) | DE3770936D1 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4931188A (en) * | 1983-10-26 | 1990-06-05 | Betz Laboratories, Inc. | Polymers for boiler water treatment |
| US5453416A (en) * | 1986-07-30 | 1995-09-26 | W. R. Grace & Co.-Conn. | Composition and method for controlling phosphonates tending to precipitate metal ions in water |
| GB8813966D0 (en) * | 1988-06-13 | 1988-07-20 | Nat Starch Chem Corp | Process for manufacture of polymers |
| DE4038106C2 (en) * | 1989-12-12 | 2002-04-18 | Siemens Ag | Surface resonator for an MRI scanner |
| DE4118634A1 (en) * | 1990-07-30 | 1992-12-10 | Uhu Gmbh | WAITER ADHESIVE SOLUTION WITHOUT ORGANIC SOLVENT |
| US5496477A (en) * | 1992-12-21 | 1996-03-05 | Ppg Industries, Inc. | Non-formaldehyde durable press finishing for cellulosic textiles with phosphinocarboxylic acid |
Family Cites Families (25)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3663448A (en) * | 1970-09-25 | 1972-05-16 | Calgon Corp | Inhibiting scale deposition |
| US3839393A (en) * | 1972-08-31 | 1974-10-01 | Alcolac Inc | Ammonium and alkali metal salts of sulfato-alkane acrylates and methacrylates |
| US3928196A (en) * | 1973-12-05 | 1975-12-23 | Calgon Corp | Inhibition of scale deposition |
| US3959167A (en) * | 1973-12-10 | 1976-05-25 | Chemed Corporation | Method and composition of inhibiting scale |
| CA1062983A (en) * | 1975-09-08 | 1979-09-25 | Joseph J. Schuck | Copolymers for the control of the formation and deposition of materials in aqueous mediums |
| US4202568A (en) * | 1975-09-25 | 1980-05-13 | Ab Gustavsberg | Tube joint |
| US4029577A (en) * | 1975-11-17 | 1977-06-14 | Betz Laboratories, Inc. | Polymers for use in water treatment |
| DE2643422A1 (en) * | 1976-09-21 | 1978-03-30 | Kurita Water Ind Ltd | WATER TREATMENT PRODUCTS AND METHODS FOR TREATMENT OF WATER |
| CA1118590A (en) * | 1979-04-05 | 1982-02-23 | Gary E. Geiger | Stable compositions for use as corrosion inhibitors |
| US4255259A (en) * | 1979-09-18 | 1981-03-10 | Chemed Corporation | Scale inhibition |
| US4306991A (en) * | 1979-09-18 | 1981-12-22 | Chemed Corporation | Scale inhibition |
| GB2061249B (en) * | 1979-10-23 | 1983-05-18 | Dearborn Chemicals Ltd | Treatment of aqueous systems to inhibit deposition of solid material |
| JPS5728112A (en) * | 1980-07-25 | 1982-02-15 | Nissan Chem Ind Ltd | Preparation of improved vinyl chloride resin |
| US4326980A (en) * | 1981-02-23 | 1982-04-27 | Betz Laboratories, Inc. | Acrylic copolymer composition inhibits scale formation and disperses oil in aqueous systems |
| US4374733A (en) * | 1981-04-01 | 1983-02-22 | Betz Laboratories, Inc. | Method for treating aqueous mediums |
| US4324664A (en) * | 1981-04-16 | 1982-04-13 | Betz Laboratories, Inc. | Method and composition for treating aqueous mediums |
| US4500693A (en) * | 1981-07-07 | 1985-02-19 | Nippon Shokubai Kagaku Kogyo Co., Ltd. | Water soluble copolymer method for manufacture therefore and use thereof |
| GB2125025B (en) * | 1982-01-29 | 1985-07-03 | Dearborn Chemicals Co | Process for inhibiting scale |
| EP0122013B1 (en) * | 1983-03-07 | 1988-12-21 | Calgon Corporation | Polymeric additives for water |
| US4530766A (en) * | 1983-04-15 | 1985-07-23 | Rohm And Haas Company | Method of inhibiting scaling in aqueous systems with low molecular weight copolymers |
| IN161206B (en) * | 1983-06-28 | 1987-10-17 | Goodrich Co B F | |
| JPS6041595A (en) * | 1983-08-15 | 1985-03-05 | Nippon Shokubai Kagaku Kogyo Co Ltd | Scale inhibitor |
| US4552665A (en) * | 1984-05-04 | 1985-11-12 | Calgon Corporation | Stabilization of soluble manganese and its reaction products |
| DE3420369C1 (en) * | 1984-06-01 | 1985-06-27 | Th. Goldschmidt Ag, 4300 Essen | Use of sulphuric acid esters of organosilicon compounds in antifreeze compositions |
| US4676911A (en) * | 1985-05-20 | 1987-06-30 | Nalco Chemical Company | Scale inhibitors which contain sulfate-containing polymers |
-
1987
- 1987-01-16 US US07/004,395 patent/US4836933A/en not_active Expired - Fee Related
- 1987-12-23 EP EP87119151A patent/EP0274733B1/en not_active Expired - Lifetime
- 1987-12-23 DE DE8787119151T patent/DE3770936D1/en not_active Expired - Fee Related
-
1988
- 1988-01-11 CA CA000556224A patent/CA1314357C/en not_active Expired - Fee Related
- 1988-01-14 JP JP63005013A patent/JPS63175698A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| US4836933A (en) | 1989-06-06 |
| EP0274733B1 (en) | 1991-06-19 |
| EP0274733A2 (en) | 1988-07-20 |
| EP0274733A3 (en) | 1989-09-06 |
| JPS63175698A (en) | 1988-07-20 |
| DE3770936D1 (en) | 1991-07-25 |
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