CA2069510A1 - Dry high flux semipermeable membranes - Google Patents

Dry high flux semipermeable membranes

Info

Publication number
CA2069510A1
CA2069510A1 CA 2069510 CA2069510A CA2069510A1 CA 2069510 A1 CA2069510 A1 CA 2069510A1 CA 2069510 CA2069510 CA 2069510 CA 2069510 A CA2069510 A CA 2069510A CA 2069510 A1 CA2069510 A1 CA 2069510A1
Authority
CA
Canada
Prior art keywords
acid
membrane
reaction product
high flux
semipermeable membranes
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.)
Granted
Application number
CA 2069510
Other languages
French (fr)
Other versions
CA2069510C (en
Inventor
Michael M. Chau
Hong C. Chu
William G. Light
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Koch Separation Solutions Inc
Original Assignee
Individual
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of CA2069510A1 publication Critical patent/CA2069510A1/en
Application granted granted Critical
Publication of CA2069510C publication Critical patent/CA2069510C/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D67/00—Processes specially adapted for manufacturing semi-permeable membranes for separation processes or apparatus
    • B01D67/0081—After-treatment of organic or inorganic membranes
    • B01D67/0088—Physical treatment with compounds, e.g. swelling, coating or impregnation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D69/00—Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/12—Composite membranes; Ultra-thin membranes
    • B01D69/125—In situ manufacturing by polymerisation, polycondensation, cross-linking or chemical reaction

Abstract

High flux semipermeable membranes which comprise the polymerized reaction product within and/or on a porous support backing material may be prepared by contacting the porous support such as a polysulfone with an aqueous solution of a polyamide which may, if so desired, contain a polar aprotic solvent not reactive with the amines, a polyhydric compound and an acid acceptor. The surface of the coated support is freed of excess solution and thereafter contacted with an organic solution of a polyacyl halide for a period of time sufficient to form a polymerized reaction product within and/or on the support material. The resulting composite is then treated with a hydroxy polycarboxylic acid, polyaminoalkylene polycarboxylic acid, sulfonic acid, amine salts of acids, amino acid, amino acid salt, polymeric acid and inorganic acid, before drying of the membrane. This will enable the membrane to be stored in a dry manner prior to use thereof in a separation process. The resultant membrane composite may be used in separation processes such as desalination of brackish or sea water or the softening of domestic hard water,
CA002069510A 1989-12-14 1990-11-30 Dry high flux semipermeable membranes Expired - Lifetime CA2069510C (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US450,637 1989-12-14
US07/450,637 US4983291A (en) 1989-12-14 1989-12-14 Dry high flux semipermeable membranes
PCT/US1990/007007 WO1991008828A1 (en) 1989-12-14 1990-11-30 Dry high flux semipermeable membranes

Publications (2)

Publication Number Publication Date
CA2069510A1 true CA2069510A1 (en) 1991-06-15
CA2069510C CA2069510C (en) 2000-05-23

Family

ID=23788905

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002069510A Expired - Lifetime CA2069510C (en) 1989-12-14 1990-11-30 Dry high flux semipermeable membranes

Country Status (14)

Country Link
US (1) US4983291A (en)
EP (1) EP0505502B1 (en)
CN (1) CN1030689C (en)
AU (1) AU639070B2 (en)
CA (1) CA2069510C (en)
DE (1) DE69003688T2 (en)
DK (1) DK0505502T3 (en)
ES (1) ES2044723T3 (en)
IE (1) IE66251B1 (en)
MX (1) MX165793B (en)
NZ (1) NZ236053A (en)
PT (1) PT96189A (en)
WO (1) WO1991008828A1 (en)
ZA (1) ZA909602B (en)

Families Citing this family (98)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ATE139713T1 (en) * 1991-03-12 1996-07-15 Toray Industries METHOD FOR PRODUCING A PARTIALLY PERMEABLE COMPOSITE MEMBRANE
US5271843A (en) * 1991-09-09 1993-12-21 Allied-Signal Inc. Chlorine-tolerant, thin-film composite membrane
US5234598A (en) * 1992-05-13 1993-08-10 Allied-Signal Inc. Thin-film composite membrane
US5395636A (en) * 1993-07-26 1995-03-07 Pall Corporation Method of pretreating a porous medium
JP3489922B2 (en) * 1994-12-22 2004-01-26 日東電工株式会社 Method for producing highly permeable composite reverse osmosis membrane
US5658460A (en) * 1996-05-07 1997-08-19 The Dow Chemical Company Use of inorganic ammonium cation salts to maintain the flux and salt rejection characteristics of reverse osmosis and nanofiltration membranes during drying
US6103121A (en) * 1996-10-31 2000-08-15 University Of Kentucky Research Foundation Membrane-based sorbent for heavy metal sequestration
US6544418B1 (en) 1996-10-31 2003-04-08 University Of Kentucky Research Foundation Preparing and regenerating a composite polymer and silica-based membrane
US6139742A (en) * 1996-10-31 2000-10-31 University Of Kentucky Research Foundation Membrane-based sorbent for heavy metal sequestration
US6306301B1 (en) 1996-10-31 2001-10-23 University Of Kentucky Research Foundation Silica-based membrane sorbent for heavy metal sequestration
WO1998041313A1 (en) * 1997-03-14 1998-09-24 Exxon Research And Engineering Company Membranes comprising aminoacid salts in polyamine polymers and blends
KR100506537B1 (en) * 1997-08-28 2005-11-08 주식회사 새 한 Manufacturing method of crosslinked polyamide reverse osmosis membrane
US6015495A (en) * 1998-02-18 2000-01-18 Saehan Industries Incorporation Composite polyamide reverse osmosis membrane and method of producing the same
US6063278A (en) * 1998-04-28 2000-05-16 Saehan Industries Inc. Composite polyamide reverse osmosis membrane and method of producing the same
US6162358A (en) * 1998-06-05 2000-12-19 Nl Chemicals Technologies, Inc. High flux reverse osmosis membrane
EP0992277B1 (en) * 1998-10-09 2004-04-07 Saehan Industries, Inc. Dry semipermeable reverse osmosis membrane and process for preparing the same using saccharides
US6368507B1 (en) 1998-10-14 2002-04-09 Saekan Industries Incorporation Composite polyamide reverse osmosis membrane and method of producing the same
US6245234B1 (en) 1999-06-03 2001-06-12 Saehan Industries Incorporation Composite polyamide reverse osmosis membrane and method of producing the same
DE19934737C2 (en) * 1999-07-23 2001-11-29 Saehan Ind Inc Polyamide reverse osmosis membrane
DE19934734C2 (en) * 1999-07-23 2002-03-07 Saehan Ind Inc Polyamide reverse osmosis membrane
US6337018B1 (en) * 2000-04-17 2002-01-08 The Dow Chemical Company Composite membrane and method for making the same
US6783711B2 (en) * 2000-05-23 2004-08-31 Ge Osmonics, Inc. Process for preparing a sulfonamide polymer matrix
US6837996B2 (en) * 2000-05-23 2005-01-04 Ge Osmonics, Inc. Polysulfonamide matrices
KR100780989B1 (en) * 2000-05-23 2007-11-29 오스모닉스 인코포레이티드 Modified Sulfonamide Polymers
RU2002134476A (en) * 2000-05-23 2004-04-10 Осмоникс, Инк. (Us) ACID RESISTANT MEMBRANES FOR NANOFILTRATION
US7001518B1 (en) * 2000-11-28 2006-02-21 Hydranautics Low pressure reverse osmosis and nanofiltration membranes and method for the production thereof
US20030015470A1 (en) * 2001-07-20 2003-01-23 Muralidhara Harapanahalli S. Nanofiltration water-softening apparatus and method
US6833073B2 (en) * 2001-10-09 2004-12-21 Pti Advanced Filtration, Inc. Composite nanofiltration and reverse osmosis membranes and method for producing the same
CA2477427A1 (en) * 2002-03-01 2003-09-12 Ge Osmonics, Inc. A process for preparing semipermeable membranes having improved permeability
WO2004078328A1 (en) * 2003-03-03 2004-09-16 General Electric Company Process for preparing semipermeable membranes
DE102004045848B3 (en) * 2004-09-20 2006-05-11 Gkss-Forschungszentrum Geesthacht Gmbh Process for producing hollow fiber membranes
JP4656503B2 (en) * 2004-10-01 2011-03-23 日東電工株式会社 Composite semipermeable membrane and method for producing the same
JP2006102594A (en) * 2004-10-01 2006-04-20 Nitto Denko Corp Method for manufacturing composite semipermeable membrane
JP4656502B2 (en) * 2004-10-01 2011-03-23 日東電工株式会社 Composite semipermeable membrane and method for producing the same
JP4656511B2 (en) * 2004-10-04 2011-03-23 日東電工株式会社 Method for producing composite reverse osmosis membrane
KR20080003789A (en) * 2005-03-09 2008-01-08 더 리전츠 오브 더 유니버시티 오브 캘리포니아 Nanocomposite membranes and methods of making and using same
US7479300B2 (en) * 2005-03-30 2009-01-20 Woongjin Chemical Co., Ltd. Composite polyamide reverse osmosis membrane and method of producing the same
MX2008000564A (en) * 2005-07-12 2008-03-10 Cargill Inc Extended-life water softening system, apparatus and method.
KR100680109B1 (en) * 2005-07-27 2007-02-07 웅진코웨이주식회사 Polyamide reverse osmosis composite membrane and preparation method thereof
US7575687B2 (en) 2005-08-16 2009-08-18 Ge Osmonics, Inc. Membranes and methods useful for caustic applications
US7909179B2 (en) * 2005-08-16 2011-03-22 Ge Osmonics, Inc. Modified polyamide matrices and methods for their preparation
US7537697B2 (en) * 2006-02-01 2009-05-26 Woongjin Chemical Co., Ltd. Selective membrane having a high fouling resistance
US7913857B2 (en) * 2006-02-01 2011-03-29 Woongjin Chemical Co., Ltd. Selective membrane having a high fouling resistance
US20070227966A1 (en) * 2006-03-31 2007-10-04 Koo Ja-Young Composite polyamide reverse osmosis membrane showing high boron rejection and method of producing the same
US7882963B2 (en) 2006-05-12 2011-02-08 Dow Global Technologies Inc. Modified membrane
CN100453153C (en) * 2006-08-17 2009-01-21 贵阳时代汇通膜科技有限公司 Extreme low-voltage composite reverse osmosis membrane and production method thereof
CN100478056C (en) * 2006-08-25 2009-04-15 贵阳时代汇通膜科技有限公司 Oxidation resistant compound reverse osmosis membrane
KR100905901B1 (en) * 2006-09-07 2009-07-02 웅진코웨이주식회사 Amine aqueous solution for forming an active layer of polyamide reverse osmosis composite membrane, polyamide reverse osmosis composite membrane prepared thereby, and preparation method thereof
JP4936438B2 (en) * 2006-10-10 2012-05-23 日東電工株式会社 Method for producing dry composite semipermeable membrane
JP2008093544A (en) * 2006-10-10 2008-04-24 Nitto Denko Corp Composite semipermeable membrane and manufacturing method thereof
JP5130967B2 (en) * 2007-03-19 2013-01-30 東レ株式会社 Manufacturing method of composite semipermeable membrane
JP2008246419A (en) * 2007-03-30 2008-10-16 Nitto Denko Corp Production method for composite semi-permeable membrane
US7910012B2 (en) * 2007-07-16 2011-03-22 General Electric Company Composition, membrane, and associated method
US20090188861A1 (en) * 2007-12-13 2009-07-30 Stc. Unm Preventing and cleaning fouling on reverse osmosis membranes
US8177978B2 (en) * 2008-04-15 2012-05-15 Nanoh20, Inc. Reverse osmosis membranes
KR20100003799A (en) 2008-07-02 2010-01-12 웅진케미칼 주식회사 Selective membrane having a high fouling resistance and preparation method thereof
US8147735B2 (en) * 2008-07-09 2012-04-03 Eltron Research & Development, Inc. Semipermeable polymers and method for producing same
WO2010050421A1 (en) * 2008-10-31 2010-05-06 東レ株式会社 Composite semipermeable membrane and manufacturing method therefor
US7815987B2 (en) * 2008-12-04 2010-10-19 Dow Global Technologies Inc. Polyamide membrane with coating of polyalkylene oxide and polyacrylamide compounds
US20100155325A1 (en) * 2008-12-24 2010-06-24 General Electric Company Particle-templated membranes, and related processes for their preparation
US8580341B2 (en) * 2009-05-22 2013-11-12 General Electric Company Method of making composite membrane
AU2010273709B2 (en) * 2009-06-29 2015-08-20 Nanoh2O, Inc. Improved hybrid TFC RO membranes with nitrogen additives
BR112012007129B1 (en) * 2009-09-29 2019-07-02 Kurita Water Industries Ltd Permeable membrane, and method for improving your rejection
WO2011112351A1 (en) * 2010-03-10 2011-09-15 Dow Global Technologies Llc Polyamide membrane with a coating comprising polyalkylene oxide and acetophenone compounds
WO2011136865A1 (en) 2010-04-26 2011-11-03 Dow Global Technologies Llc Polyamide membrane with a coating comprising polyalkylene oxide and triazine compounds
WO2011149572A1 (en) 2010-05-24 2011-12-01 Dow Global Technologies Llc Polyamide membrane with coating comprising polyalkylene oxide and imidazol compounds
US8733558B2 (en) 2010-05-24 2014-05-27 Dow Global Technologies Llc Composite membrane with coating comprising polyalkylene oxide and biguanide-type compounds
US8757396B2 (en) 2010-05-24 2014-06-24 Dow Global Technologies Llc Composite membrane with coating comprising polyalkylene oxide and oxy-substituted phenyl compounds
EP2637773B1 (en) 2010-11-10 2019-10-30 NanoH2O Inc. Improved hybrid tfc ro membranes with non-metallic additives
US20120152839A1 (en) * 2010-12-20 2012-06-21 David Allen Olson Modified sulfonamide polymeric matrices
US8820540B2 (en) 2011-01-28 2014-09-02 Woongjin Chemical Co., Ltd. Method for preparing a filtration membrane and filtration membrane prepared by said method
KR101240956B1 (en) 2011-02-18 2013-03-11 웅진케미칼 주식회사 Reverse osmosis composite having high fouling resistance and manufacturing method thereof
JP5914973B2 (en) * 2011-03-09 2016-05-11 栗田工業株式会社 Method for improving rejection rate of permeable membrane and treatment agent for improving rejection rate
JP5929296B2 (en) * 2012-02-21 2016-06-01 栗田工業株式会社 Reverse osmosis membrane rejection improvement method
BR112013022550B1 (en) * 2011-03-09 2020-10-20 Kurita Water Industries Ltd method to improve the rejection of a reverse osmosis membrane and use of an aqueous solution to improve the rejection of a reverse osmosis membrane
JP5772083B2 (en) * 2011-03-09 2015-09-02 栗田工業株式会社 Reverse osmosis membrane rejection rate improving method, rejection rate improving treatment agent, and reverse osmosis membrane
WO2012161483A2 (en) * 2011-05-20 2012-11-29 주식회사 엘지화학 Method for preparing a reverse osmosis membrane, and reverse osmosis membrane prepared thereby
CN102179191A (en) * 2011-05-31 2011-09-14 南京帝膜净水材料开发有限公司 Method for manufacturing anti-chloride polyamide reverse osmosis composite membrane with high flux
CN102274696A (en) * 2011-05-31 2011-12-14 南京帝膜净水材料开发有限公司 Method for preparing polyamide reverse osmosis composite membrane
CN102284254B (en) * 2011-06-10 2013-06-19 南京帝膜净水材料开发有限公司 Method for manufacturing chlorine-resistant polyamide reverse osmosis composite film
KR101412563B1 (en) * 2012-05-24 2014-07-02 주식회사 엘지화학 Method of manufacturing reverse osmosis membrane and reverse osmosis membrane manufactured thereby
KR101432219B1 (en) * 2012-05-24 2014-08-21 주식회사 엘지화학 Reverse osmosis membrane
CN105188891B (en) 2013-03-14 2017-11-24 陶氏环球技术有限责任公司 Include the composite polyamide membranes of soluble polymer coating
CN103212312B (en) * 2013-04-28 2018-03-02 中国科学院化学研究所 A kind of Asymmetric antioxidant permeable membrane and preparation method thereof
US9795928B2 (en) 2014-06-24 2017-10-24 Nano And Advanced Materials Institute Limited Stepwise interfacial polymerization technique with different reagent solution designs to prepare hollow fiber nanofiltration membrane composites
CN104437106A (en) * 2014-11-26 2015-03-25 北京碧水源膜科技有限公司 Preparation method of nano-filtration membrane
US9695065B2 (en) 2015-06-03 2017-07-04 Lg Nanoh2O, Inc. Combination of chemical additives for enhancement of water flux of a membrane
US9731985B2 (en) 2015-06-03 2017-08-15 Lg Nanoh2O, Inc. Chemical additives for enhancement of water flux of a membrane
US9724651B2 (en) 2015-07-14 2017-08-08 Lg Nanoh2O, Inc. Chemical additives for water flux enhancement
US9861940B2 (en) 2015-08-31 2018-01-09 Lg Baboh2O, Inc. Additives for salt rejection enhancement of a membrane
KR101946983B1 (en) * 2015-09-08 2019-02-12 주식회사 엘지화학 Method for manufacturing water-treatment membrane, water-treatment membrane manufactured by thereof, and water treatment module comprising membrane
CN105396471A (en) * 2015-12-19 2016-03-16 杭州水处理技术研究开发中心有限公司 Preparation method of high water flux reverse osmosis membrane
US9737859B2 (en) 2016-01-11 2017-08-22 Lg Nanoh2O, Inc. Process for improved water flux through a TFC membrane
US10155203B2 (en) 2016-03-03 2018-12-18 Lg Nanoh2O, Inc. Methods of enhancing water flux of a TFC membrane using oxidizing and reducing agents
CN107456871B (en) * 2017-08-02 2020-10-30 同济大学 Preparation method of hollow fiber composite loose nanofiltration membrane
WO2020006019A1 (en) 2018-06-27 2020-01-02 Lubrizol Advanced Materials, Inc. Flat sheet porous pvc membrane
AU2020307405A1 (en) 2019-06-24 2022-01-20 Lubrizol Advanced Materials, Inc. Hollow fiber membrane
CN113398781B (en) * 2021-06-18 2022-07-19 中国农业科学院农业质量标准与检测技术研究所 Microporous filter membrane material and preparation method and application thereof

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3744642A (en) * 1970-12-30 1973-07-10 Westinghouse Electric Corp Interface condensation desalination membranes
US4259183A (en) * 1978-11-07 1981-03-31 Midwest Research Institute Reverse osmosis membrane
US4277344A (en) * 1979-02-22 1981-07-07 Filmtec Corporation Interfacially synthesized reverse osmosis membrane
JPS5727102A (en) * 1980-07-28 1982-02-13 Nitto Electric Ind Co Ltd Composite semipermeable membrane and its production
US4606943A (en) * 1983-03-18 1986-08-19 Culligan International Company Method for preparation of semipermeable composite membrane
US4609468A (en) * 1984-06-01 1986-09-02 Uop Inc. Increased strength polymer-blended membranes
US4520044A (en) * 1984-07-30 1985-05-28 E. I. Du Pont De Nemours And Company Production of composite membranes
US4851127A (en) * 1984-11-23 1989-07-25 Bend Research, Inc. Novel amine-based presursor compounds and composite membranes thereof
US4885091A (en) * 1984-12-26 1989-12-05 Allied-Signal Inc. Process for the preparation of chlorine-resistant semipermeable membranes
US4919808A (en) * 1985-10-21 1990-04-24 Allied-Signal Inc. Semipermeable membrane compositions
US4747953A (en) * 1986-02-21 1988-05-31 Allied Corporation Composite membranes based on interpenetrating polymer networks
US4765897A (en) * 1986-04-28 1988-08-23 The Dow Chemical Company Polyamide membranes useful for water softening
US4814082A (en) * 1986-10-20 1989-03-21 Memtec North America Corporation Ultrafiltration thin film membranes
US4830885A (en) * 1987-06-08 1989-05-16 Allied-Signal Inc. Chlorine-resistant semipermeable membranes
US4828700A (en) * 1987-07-20 1989-05-09 The Dow Chemical Company Rejection enhancing coatings for reverse osmosis membranes
US4828708A (en) * 1987-09-28 1989-05-09 Desalination Systems Semipermeable membranes

Also Published As

Publication number Publication date
AU7072191A (en) 1991-07-18
EP0505502B1 (en) 1993-09-29
DE69003688D1 (en) 1993-11-04
CA2069510C (en) 2000-05-23
ES2044723T3 (en) 1994-01-01
US4983291A (en) 1991-01-08
PT96189A (en) 1991-09-30
NZ236053A (en) 1992-02-25
IE66251B1 (en) 1995-12-27
CN1030689C (en) 1996-01-17
MX165793B (en) 1992-12-03
EP0505502A1 (en) 1992-09-30
IE904014A1 (en) 1991-06-19
DE69003688T2 (en) 1994-01-27
WO1991008828A1 (en) 1991-06-27
AU639070B2 (en) 1993-07-15
DK0505502T3 (en) 1994-03-21
CN1054200A (en) 1991-09-04
ZA909602B (en) 1991-11-27

Similar Documents

Publication Publication Date Title
CA2069510A1 (en) Dry high flux semipermeable membranes
US4950404B1 (en)
US3808305A (en) Crosslinked,interpolymer fixed-charge membranes
US4012324A (en) Crosslinked, interpolymer fixed-charge membranes
US6833073B2 (en) Composite nanofiltration and reverse osmosis membranes and method for producing the same
US4872984A (en) Interfacially synthesized reverse osmosis membrane containing an amine salt and processes for preparing the same
ATE82703T1 (en) CHLORINE RESISTANT SEMI-PERMEABLE MEMBRANES.
US5744039A (en) Composite semipermeable membrane and production method thereof
US4828708A (en) Semipermeable membranes
CN105396472A (en) Preparation method of composite base-membrane nanofiltration membrane
ATE40952T1 (en) COMPOSITE MATERIAL, PROCESS FOR ITS PRODUCTION AND ITS USE IN OSMOTIC PURIFICATION OF LIQUIDS.
EP0308153B1 (en) P-xylylenediamide/diimide composite ro membranes
US7658872B2 (en) Process for preparing semipermeable membranes having improved permeability
DE3564077D1 (en) Semipermeable composite membrane
KR100666483B1 (en) Producing method of polyamide reverse osmosis membrane having high salt rejection property
JPS6418406A (en) Permselective hollow yarn composite membrane and production thereof
KR19980068304A (en) Performance Improvement Method of Polyamide Reverse Osmosis Composite Membrane
KR20030022915A (en) Producing method of composite polyamide reverse osmosis membrane
GB2139113A (en) Reverse osmosis membrane and method for the preparation thereof
DK0467903T3 (en) Process for the preparation of a chlorine-resistant semi-permeable polyester membrane
JPS5549106A (en) Selective permeable composite membrane and production thereof
JPS57159503A (en) Composite semi-permeable membrane and preparation thereof
JPS5712801A (en) Dynamic membrane for water treatment
JPS59173185A (en) Selective separation
JPH11169689A (en) Method for evaluating performance of composite reverse osmosis membrane and treatment of liquid using same

Legal Events

Date Code Title Description
EEER Examination request
MKLA Lapsed
MKEC Expiry (correction)

Effective date: 20121202