GB2086954A - Ion Exchange Filter Medium and Process for Producing the Same - Google Patents

Ion Exchange Filter Medium and Process for Producing the Same Download PDF

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Publication number
GB2086954A
GB2086954A GB8130755A GB8130755A GB2086954A GB 2086954 A GB2086954 A GB 2086954A GB 8130755 A GB8130755 A GB 8130755A GB 8130755 A GB8130755 A GB 8130755A GB 2086954 A GB2086954 A GB 2086954A
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United Kingdom
Prior art keywords
ion exchange
filter medium
fibers
fiber
poly
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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.)
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Application number
GB8130755A
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Sumitomo Chemical Co Ltd
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Sumitomo Chemical Co Ltd
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Filing date
Publication date
Application filed by Sumitomo Chemical Co Ltd filed Critical Sumitomo Chemical Co Ltd
Publication of GB2086954A publication Critical patent/GB2086954A/en
Withdrawn legal-status Critical Current

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Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H5/00—Special paper or cardboard not otherwise provided for
    • D21H5/12—Special paper or cardboard not otherwise provided for characterised by the use of special fibrous materials
    • D21H5/20—Special paper or cardboard not otherwise provided for characterised by the use of special fibrous materials of organic non-cellulosic fibres too short for spinning, with or without cellulose fibres
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J47/00—Ion-exchange processes in general; Apparatus therefor
    • B01J47/12—Ion-exchange processes in general; Apparatus therefor characterised by the use of ion-exchange material in the form of ribbons, filaments, fibres or sheets, e.g. membranes
    • B01J47/127—Ion-exchange processes in general; Apparatus therefor characterised by the use of ion-exchange material in the form of ribbons, filaments, fibres or sheets, e.g. membranes in the form of filaments or fibres
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
    • C22B3/20—Treatment or purification of solutions, e.g. obtained by leaching
    • C22B3/42—Treatment or purification of solutions, e.g. obtained by leaching by ion-exchange extraction
    • 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
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Materials Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Geology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Manufacturing & Machinery (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Filtering Materials (AREA)
  • Manufacture Of Macromolecular Shaped Articles (AREA)
  • Paper (AREA)
  • Treatment Of Water By Ion Exchange (AREA)

Abstract

An ion exchange filter medium comprising poly(vinyl alcohol) series ion exchange fibers having one or more ion exchange groups selected from a sulfonic acid group, a carboxyl group, an iminodicarboxyl group, a quaternary ammonium salt group and an amino group and, optionally, together with one or more thermoplastic synthetic fibers and/or natural fibers can rapidly and completely capture ions derived from Cr, Cd, Ca, P, etc. in water.

Description

SPECIFICATION lon Exchange Filter Medium and Process for Producing the Same This invention relates to ion exchange filter medium for selectively capturing ions in water which comprises poly(vinyl alcohol) series ion exchange fibers and to a process for producing said filter medium.
In recent years, water pollution has been increasing and taken as a serious problem from the standpoint of environmental conservation. As a result, effluent standards and environmental quality standards have been provided. These regulations are considered to become strict more and more in the future. In industries such as chemical, metal, iron and steel, electric machinery, etc., consuming large amounts of water, waste water often contains harmful ions such as those of chromium, cadmium, nickel, cyanide, arsenic, or phosphorous and techniques to remove and analyze such ions are regarded important for prevention of environmental pollution.
As ion capturing filter media, there are known fabrics coated with fine powders of ion exchange resins and filter papers, which are prepared by paper-making process from blends of ion exchange resin powders and wood pulps. These types of filter media, however, have questions in ion exchange rate and contact area, and difficulty in capturing ions completely, and are deficient in practical use.
In view of the above, the present inventors noted (1) wide contact surface areas of ion exchange fibers and (2) their high rates of ion exchange, and as a result developed an ion exchange filter medium having selectivity and exhibiting a high rate of ion exchange. Thus, the present invention has been accomplished.
The invention provides an ion exchange filter medium capable of capturing trace amounts of anions or cations selectively which comprises poly(vinyl alcohol) series ion exchange fibers and also provides a process for producing the same.
The poly(vinyl alcohol) series ion exchange fibers to be used in this invention should have one or more ion exchange groups selected from a sulfonic acid group (-SO3H), a carboxyl group (-COOH), an amino group (-NH2), a quaternary ammonium salt group [-N+(R)3X- wherein R is alkyl, and X is halogen], and an iminodicarboxyl group
wherein n is an integer of 1 to 2].
The ion exchange fibers can be prepared in known ways, for example, by treating a poly(vinyl alcohol) series fibers converted to have a partial polyene structure with sulfuric acid to introduce sulfonic acid groups into remaining hydroxyl groups; by adding chlorine to the polyene structure of the fibers, followed by treatment with ammonia, trimethylamine or the like to introduce amino groups or quaternary ammonium salt groups thereinto; by treating the fibers with monochloroacetic acid in the presence of sodium hydroxide to introduce carboxyl groups into remaining hydroxyl groups; by treating the fibers with epichlorohydrin and iminodiacetic acid in the presence of sodium hydroxide to introduce iminodicarboxylic acid groups into remaining hydroxyl groups; and the like.
While any form of poly(vinyi alcohol) series ion exchange fibers may be used in this invention, suitable forms are 0.05 - y, preferably 0.1 - 20 , in fiber diameter and 0.2 - 10 mm, preferably 0.5 - 5 mm, in fiber length. Either too short or too long fiber lengths or too large fiber diameters are unfavorable since these make difficult the conversion of fibers to filter media.
Ion exchange capacity of the poly(vinyl alcohol) series ion exchange fibers used in this invention, which varies depending upon types of ion exchange groups of the fiber, is 2-6 meq/g for a strong acid type cation exchange fiber (sulfonic acid group), 1-3 meq/g for a strong base type anion exchange fiber (quaternary ammonium salt group) 3-8 meq/g for a weak acid type cation exchange fiber (carboxyl group), 5-10 meq/g for a weak base type anion exchange fiber (amino group) and 0.5-2 meq/g for a cheiate type fiber (iminodicarboxyl radical). Needless to say, higher ion exchange capacity is the more favorable in this invention; fibers of too low ion exchange capacity are undesirable because their ion exchange capacity per unit weight of ion exchange filter medium is undesirably lowered.
The poly(vinyl alcohol) series ion exchange fibers mentioned above can be used as they are as ion exchange medium, but is preferably served as an ion exchange filter medium in combination with thermoplastic synthetic fibers and/or natural fibers in consideration of mechanical strength or other properties of the filter medium and possible service conditions. As examples of the thermoplastic synthetic fiber usable in this invention, there may be cited those of polyethylene, polyamide, and the like. Examples of the natural fiber are cotton linter pulp, etc.
The ion exchange filter medium of this invention is desirable to have a filter paper-like form. Such a form of filter medium can be produced from the present ion exchange fiber by usual methods such as a paper-making process, a weaving process, and a nonwoven fabric making process by use of binder or by sintering.
It is important in any of these processes to provide the filter medium with both suitable water permeability and water resistance without reducing the effective contact area greatly.
Of these processes the paper-making process is most suited. When this process is applied, the filter medium of this invention can be produced with or without blending other fibers such as synthetic pulps, synthetic fibers (e.g., polyethylene fiber, polypropylene fiber), natural pulps, or natural fibers (e.g., cotton). It is also possible in this case to add a binder, e.g., starch, poly(ethylene oxide), etc.
The ion exchange fiber content in the filter medium is suitably 4090% by weight, preferably 50-70% by weight Lower content of ion exchange fiber is undesirable because of lowering in ion exchange capacity per unit weight of filter medium. On the other hand, higher content of ion exchange fiber is also undesirable because of lowering in strength of the resulting filter medium.
The control of water permeability of the filter medium is achievable by adjusting the degree of beating of the fiber, i.e., synthetic pulp, synthetic fiber, natural pulp, or natural fiber, to be added, and the basis weight and thickness of the filter medium. When thermoplastic fibers such as synthetic pulp or synthetic fiber is blended, the water permeability control and water resistance improvement can be achieved by a heat treatment.
Said heat treatment means an operation for compacting the web, made from said fibers, with pressure by use of a heat press or heat roll. The suited pressure of the heat treatment is selected from the range of 1-100 Kg/cm2 per unit area of filter medium and preferable pressure may be decided depending upon the blending ratio of thermoplastic fiber and its heat treatment temperature.
While said heat treatment may be practiced in either the wet or dry state after sheeting of blended fibers, wet operation is more effective.
Suitable temperature for the heat treatment are different in the cases of production of cation exchange filter medium and the production of anion exchange filter medium. The suited temperature of the heat treatment is 100- 2000C, particularly 130-1 600 C, for the production of cation exchange filter medium, and 100--1 500C, particularly 1 250C, for the production of anion exchange filter medium.
Too high temperatures in the heat treatment are undesirable because of causing the decomposition of the ion exchange groups. In particular, in the case of strong base type (quaternary ammonium salt group) it is preferable to conduct the heat treatment at lower temperatures. Too low temperatures of the heat treatment are also undesirable since sufficient heat treatment effects cannot be obtained.
Suitable thickness of the ion exchange filter medium of this invention ranges from 0.05 to 5 mm, more preferably from 0.1 to 0.5 mm. Either a too thin or too thick filter medium is undesirable since the former is inferior in ion exchange capacity and the later exhibits a poor water permeability.
Water permeability of the present filter medium is generally 0.05-10 ml/min, preferably 0.2-3 ml/min, per cm2 of filter medium surface under a pressure of 100 cm H20. When the water permeability is too low, too long time is required for filtration, and when too high, complete capture of ions is undesirably difficult.
Characteristics of this invention in the production of ion exchange filter medium are based on the use of a novel polyvinyl alcohol series ion exchange fibers, sheeting of blends of the ion exchange fibers with other fibers such as synthetic pulp, synthetic fiber, natural pulp, or natural fiber, and a subsequent heat treatment of the resulting web to control the water permeability of the product filter medium.
The ion exchange filter medium according to this invention captures ions in water for example, Ca++, P043-, Cr++, Cr+++, Ca++, Ni++, etc., rapidly and completely, so that it will make many contributions to the prevention of environmental pollution and the effective utilization of sources as well as to the progress of analytical techniques, for example, to simplification and time-saving of ion collecting procedure, when it is used as a filter medium for analysis.
The ion exchange filter medium according to this invention can be used, for example, in the following analysis since it is characterized by rapid and complete capturing of ions: (1) After ions in a sample have been collected by filtering the sample through the present filter medium, the captured ions are determined as such by fluoroescent X-ray analysis.
(2) After ions in a sample have been collected in the filter medium, the captured ions are eluted with an acid such as hydrochloric acid, concentrated, and determined by atomic absorption spectroscopy or absorptiometry.
In any case, by the use of the ion exchange filter medium, analytical procedures can be by far simplified with a shorter time compared with the case of not using the ion exchange filter medium of the present invention.
The present invention will be illustrated by way of the following examples; which do not iimit the scope of the invention.
Example 1 5 Grams of a strong acid type of cation exchange fiber (trade name: IEF-SC, containing sulfonic acid groups, a neutral salt decomposition capacity of 2.7 meq/g, manufactured by Nichibi K.K.), 2.5 g of polyethylene pulp (trade name: Mitsui-Zellabach E-400, produced by Mitsui Zellabach K.K.). 2.5 g of filter paper (trade name: Toyo Roshi No. 131, produced by Toyo Filter Paper Co., Ltd.), and 1 liter of water were mixed in a mixer, and the mixture was made into sheets by; using a square sheet making machine (sheet size: 25 cmx25 cm, manufactured by Kumagai Riki Kogyo K.K.). The sheets were dehydrated by pressing and further wet pressed by applying a pressure of 50 Kg/cm2 at 1 500C for 4 minutes.
The water permeability of the resultant filter paper-like sheets was 0.7 ml/cm2.min under a pressure of 100 cm H20.
From these sheets, circular pieces of each 47 mm in diameter (neutral salts decomposition capacity: 0.37 meq/piece) were punched off. An aqueous solution in an amount of 500 ml containing 100 yg of Ca++ ions was filtered through this circular sheet with suction for 30 minutes.
On analyzing the filtrate by atomic absorption spectrascopy, no Ca++ ion was detected therein.
Example 2 5 Grams of a strong base type of anion exchange fiber (trade name; 1 EF-SA, a quaternary ammonium salt group-containing fiber with a neutral salt decomposition capacity of 1.4 meq/g, manufactured by Nichibi K.K.). 5 g of the same polyethylene pulp as used in Example 1, and 1 liter of water were mixed in a mixer and the mixture was made into sheets by using the same sheet making machine as used in Example 1. The sheets were dehydrated by pressing and further wet pressed by applying a pressure of 50 Kg/cm2 at 1 200C for 4 minutes.
The water permeability of the resultant filter paper-like sheets was 0.5 ml/cm2.min under pressure of 100 cm H20.
From these sheets, circular pieces of each 47 mm in diameter (neutral salts decomposition capacity 0.19 meq/piece) were punched off. An aqueous solution in an amount of 100 ml containing P043- ions in an amount of 100 ,ug as P was filtered through this circular sheet with suction for 10 minutes. Analysis of the filtrate by absorptiomerty showed that 92% or more of Pro43~ ions was captured by the sheet.

Claims (14)

Claims
1. An ion exchange filter medium comprising poly(vinyl alcohol) series ion exchange fibers having one or more ion exchange groups selected from a sulfonic acid group (-SO3H), a carboxyl group (-COOH), an imino dicarboxyl group
wherein n is an integer of 1 to 2], a quaternary ammonium salt group (-N+(R)3X wherein R is alkyl and X is halogen), and an amino group (-NH2), and optionally one or more thermoplastic synthetic fibers and/or natural fibers.
2. An ion exchange filter medium according to claim 1, wherein said thermoplastic synthetic fiber is polyethylene fiber.
3. An ion exchange filter medium according to claim 1 or 2, wherein said natural fiber is cotton linter pulp.
4. An ion exchange filter medium according to any one of the preceding claims, wherein said poly(vinyl alcohol) series ion exchange fibers are contained in the medium in an amount of 40% by weight or more.
5. An ion exchange filter medium according to any one of the preceding claims, wherein said poly(vinyl alcohol) series ion exchange fibers have a form of 0.05-50 ,u in fiber diameter and 0.210 mm in fiber length.
6. An ion exchange filter medium according to any one of the preceding claims, wherein said poly(vinyl alcohol) series ion exchange fibers have suifonic acid groups as ion exchange groups.
7. An ion exchange filter medium according to any one of claims 1 to 5, wherein said poly(vinyl alcohol) series ion exchange fibers have quaternary ammonium salt groups as ion exchange groups.
8. An ion exchange filter medium according to claim 1 substantially as hereinbefore described with reference to any one of the Examples.
9. A process for producing a filter paper-like ion exchange filter medium which comprises subjecting poly(vinyl alcohol) series ion exchange fibers having one or more groups selected from a sulfonic acid group (-SO3H), a carboxyl group (-COOH), an iminodicarboxyl group
wherein n is an integer of 1 to 2), a quaternary ammonium salt group (-N+(R)3X wherein R is alkyl and X is halogen), and an amino group (-N H2) to a paper-making process together with one or more thermoplastic synthetic fibers and/or natural fibers, and heat treating the resulting paper under pressure.
10. A process according to claim 9, wherein said filter medium contains the poly(vinyl alcohol) series ion exchange fibers in an amount of 4090% by weight.
11. A process according to claim 9 or 10, wherein said heat treatment under pressure is conducted at a pressure of 1-100 Kg/cm2 and at a temperature of 100--2000C to produce a cation exchange filter medium or 100-1 500C to produce an exchange filter medium.
12. A process according to any one of claims 9 to 11, wherein the thermoplastic synthetic fiber is polyethylene fiber.
1 3. A process according to any one of claims 9 to 12, wherein the natural fiber is cotton linter pulp.
14. A process according to any one of claims 9 to 13, wherein the poly(vinyl alcohol) series ion exchange fibers have a form of 0.05-50,u in fiber diameter and 0.2-10 mm in fiber length.
1 5. A process'according to any one of claims 9 to 14, wherein the ion exchange fibers have sulfonic acid groups or quaternary ammonium groups as ion exchange groups.
1 6. A process according to claim 9 substantially as hereinbefore described with reference to any one of the Examples.
1 7. A method of removing ions from solution which comprises bringing an ion containing liquid into contact with an ion exchange filter medium according to any one of claims 1 to 8 and separating the loaded medium from the liquid of reduced ion concentration.
1 8. A method according to claim 17, wherein the ion containing liquid is an aqueous solution containing environmentally polluting ions.
GB8130755A 1980-10-13 1981-10-12 Ion Exchange Filter Medium and Process for Producing the Same Withdrawn GB2086954A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP55143391A JPS5767634A (en) 1980-10-13 1980-10-13 Ion-exchange filter and its preparation

Publications (1)

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GB2086954A true GB2086954A (en) 1982-05-19

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GB8130755A Withdrawn GB2086954A (en) 1980-10-13 1981-10-12 Ion Exchange Filter Medium and Process for Producing the Same

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JP (1) JPS5767634A (en)
DE (1) DE3140445A1 (en)
FR (1) FR2491779A1 (en)
GB (1) GB2086954A (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2190689A (en) * 1986-05-19 1987-11-25 Nat Res Dev Blended fibre filter material
EP0621072A2 (en) * 1993-04-21 1994-10-26 Nippon Rensui Co. Demineralization apparatus comprising a diluting chamber packed with a cloth
EP1367086A1 (en) * 2001-07-30 2003-12-03 Asahi Glass Engineering Co.,Ltd. Anion exchanger and process for producing anion exchange membrane
EP1681273A1 (en) 2001-11-27 2006-07-19 Reckitt Benckiser N.V. Water-softening tablet
EP1990319A2 (en) 2003-07-07 2008-11-12 Reckitt Benckiser N.V. Water-softening method
US7695523B2 (en) 2002-03-22 2010-04-13 Reckitt Benckiser N.V. Cleaning method
CN114007743A (en) * 2019-06-20 2022-02-01 日本爱克兰工业株式会社 Ion exchange fiber and ion exchange filter containing the same

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60147643U (en) * 1984-03-12 1985-10-01 三菱製紙株式会社 ion exchange sheet
GB8506361D0 (en) * 1985-03-12 1985-04-11 Courtaulds Plc Cationic fibre
FR2657076B1 (en) * 1990-01-15 1992-09-04 Inst Textile De France USE OF GRAFT CELLULOSE FOR THE PURIFICATION OF WATER.
DE4110736A1 (en) * 1991-04-03 1992-10-08 Rotta Innovations Gmbh Dr Heat degradable polymer particles used in water treatment - comprising amino resin matrix with immobilised functional polymer

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3028296A (en) * 1958-10-20 1962-04-03 American Can Co Fibrous sheet material
FR1252291A (en) * 1959-02-27 1961-01-27 Kurashiki Rayon Co Papers and nonwoven fabrics containing polyvinyl alcohol fibers
GB1487995A (en) * 1974-11-21 1977-10-05 Tullis Russell Co Ltd Filter papers
JPS534787A (en) * 1976-07-05 1978-01-17 Nichibi Kk Cation exchange fibers and its manufacture
GB2016473B (en) * 1979-03-06 1982-09-02 Sumitomo Chemical Co Cellulosic ion-exchange fibres

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2190689A (en) * 1986-05-19 1987-11-25 Nat Res Dev Blended fibre filter material
US4798850A (en) * 1986-05-19 1989-01-17 National Research Development Corporation Blended-fibre filter material
GB2190689B (en) * 1986-05-19 1989-12-06 Nat Res Dev Blended-fibre filter material
EP0621072A2 (en) * 1993-04-21 1994-10-26 Nippon Rensui Co. Demineralization apparatus comprising a diluting chamber packed with a cloth
EP0621072A3 (en) * 1993-04-21 1994-12-28 Nippon Rensui Kk Demineralization apparatus and cloth for packing diluting chamber of the demineralization apparatus.
US5512173A (en) * 1993-04-21 1996-04-30 Nippon Rensui Co. Demineralization apparatus and cloth for packing diluting chamber of the demineralization apparatus
EP1367086A1 (en) * 2001-07-30 2003-12-03 Asahi Glass Engineering Co.,Ltd. Anion exchanger and process for producing anion exchange membrane
US6780893B2 (en) 2001-07-30 2004-08-24 Asahi Glass Engineering Co., Ltd. Anion exchanger and process for producing anion exchange membrane
EP1681273A1 (en) 2001-11-27 2006-07-19 Reckitt Benckiser N.V. Water-softening tablet
US7695523B2 (en) 2002-03-22 2010-04-13 Reckitt Benckiser N.V. Cleaning method
EP1990319A2 (en) 2003-07-07 2008-11-12 Reckitt Benckiser N.V. Water-softening method
CN114007743A (en) * 2019-06-20 2022-02-01 日本爱克兰工业株式会社 Ion exchange fiber and ion exchange filter containing the same
CN114007743B (en) * 2019-06-20 2023-09-15 日本爱克兰工业株式会社 Ion exchange fiber and ion exchange filter containing the same

Also Published As

Publication number Publication date
JPS5767634A (en) 1982-04-24
FR2491779A1 (en) 1982-04-16
DE3140445A1 (en) 1982-06-09

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