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EP2611528A1 - Filtration material for desalination - Google Patents
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EP2611528A1 - Filtration material for desalination - Google Patents

Filtration material for desalination

Info

Publication number
EP2611528A1
EP2611528A1 EP11821071.5A EP11821071A EP2611528A1 EP 2611528 A1 EP2611528 A1 EP 2611528A1 EP 11821071 A EP11821071 A EP 11821071A EP 2611528 A1 EP2611528 A1 EP 2611528A1
Authority
EP
European Patent Office
Prior art keywords
desalination
filtration material
water
cross
swellable 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.)
Withdrawn
Application number
EP11821071.5A
Other languages
German (de)
French (fr)
Other versions
EP2611528A4 (en
Inventor
Shu-Hui Cheng
Jong-Pyng Chen
En Kuang Wang
Yi-Chun Lo
Shan-shan LIN
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.)
Industrial Technology Research Institute ITRI
Original Assignee
Industrial Technology Research Institute ITRI
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 Industrial Technology Research Institute ITRI filed Critical Industrial Technology Research Institute ITRI
Publication of EP2611528A1 publication Critical patent/EP2611528A1/en
Publication of EP2611528A4 publication Critical patent/EP2611528A4/en
Withdrawn legal-status Critical Current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
    • B01D67/0002—Organic membrane manufacture
    • B01D67/0006—Organic membrane manufacture by chemical reactions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D39/00—Filtering material for liquid or gaseous fluids
    • B01D39/14—Other self-supporting filtering material ; Other filtering material
    • B01D39/16—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres
    • B01D39/1692—Other shaped material, e.g. perforated or porous sheets
    • 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
    • B01D69/1216—Three or more layers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06—Organic material
    • B01D71/08—Polysaccharides
    • B01D71/12—Cellulose derivatives
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06—Organic material
    • B01D71/26—Polyalkenes
    • B01D71/262—Polypropylene
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06—Organic material
    • B01D71/28—Polymers of vinyl aromatic compounds
    • B01D71/281—Polystyrene
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06—Organic material
    • B01D71/38—Polyalkenylalcohols; Polyalkenylesters; Polyalkenylethers; Polyalkenylaldehydes; Polyalkenylketones; Polyalkenylacetals; Polyalkenylketals
    • B01D71/381—Polyvinylalcohol
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D71/00—Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06—Organic material
    • B01D71/40—Polymers of unsaturated acids or derivatives thereof, e.g. salts, amides, imides, nitriles, anhydrides, esters
    • B01D71/42—Polymers of nitriles, e.g. polyacrylonitrile
    • B01D71/421—Polyacrylonitrile
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/02—Types of fibres, filaments or particles, self-supporting or supported materials
    • B01D2239/025—Types of fibres, filaments or particles, self-supporting or supported materials comprising nanofibres
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/02—Types of fibres, filaments or particles, self-supporting or supported materials
    • B01D2239/0291—Types of fibres, filaments or particles, self-supporting or supported materials comprising swelling polymers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2323/00—Details relating to membrane preparation
    • B01D2323/30—Cross-linking
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2323/00—Details relating to membrane preparation
    • B01D2323/39—Electrospinning
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
    • C02F2103/08—Seawater, e.g. for desalination
    • 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
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A20/00—Water conservation; Efficient water supply; Efficient water use
    • Y02A20/124—Water desalination
    • Y02A20/131—Reverse-osmosis

Definitions

  • the present invention relates to a filtration material for desalination, and in particular relates to a filtration material made of a water- swellable polymer.
  • US Patent No.4828700 discloses a membrane made of cross-linked poly methyl methacrylate.
  • the membrane performance has a 9.1 GFD flux, and a 97.9 % salt rejection, when tested under an operation pressure of 400 psi using 2500 ppm of salt water.
  • US Patent No.5755964 discloses a reverse osmosis (RO) membrane, wherein the RO membrane has good wetting property by using an amine compound to treat the surface of the RO membrane.
  • the RO membrane performance has a 48 GFD flux, when tested under an operation pressure of 225 psi using 2000 ppm of salt water.
  • the RO membrane exhibits high flux like nanofiltration material.
  • the filtration materials for desalination in prior art are made of nanoporous polymeric thin film.
  • the nanoporous polymeric thin film must be operated under a high pressure.
  • the operation pressure may be decreased, which would thereby improve desalination efficiency.
  • the present invention provides a filtration material for desalination, comprising: a support layer, and a desalination layer formed on the support layer, wherein the desalination layer is a fiber composite membrane and comprises at least one water- swellable polymer.
  • the invention provides a filtration material for desalination, which comprises a support layer and a desalination layer formed on the support layer.
  • the support layer is used to support the desalination layer.
  • the desalination layer is a fiber composite membrane and comprises at least one water- swellable polymer.
  • water-swellable polymer means that the polymer can swell itself by absorbing water. Although the polymer absorbs a lot of water, the structure of the polymer is not deformed. In some cases, the water-swellable polymer is not a water soluble polymer and is made of hydrophilic monomers and hydrophobic monomers. Alternatively, the water-swellable polymer is a water soluble polymer, and it maintains the swellable property and reduces the hydrolysis property by an appropriate cross-linking reaction.
  • the support layer comprises one or more porous materials, wherein the porous materials comprise cellouse ester, poly sulf one, polyacrylonitrile (PAN), polyvinglidene fluoride (PVDF), polyetheretherketone (PEK), polyester (PET), polyimide (PI), chlorinated polyvinyl chloride (PVC) or styrene acrylnitrile (SAN).
  • the support layer may be self- made or commercially available and may be in the form of non-woven, woven or open pores.
  • the filtration material for desalination comprises two support layers in which a bottom layer is polyester (PET), and an upper layer is polyacrylonitrile (PAN) or polysulfone.
  • the two support layers may be in the form of a non- woven or woven layer, and preferably non- woven layer.
  • the hydrophilic monomers of the water- swellable polymer comprise ionic monomers and non-ionic monomers.
  • the ionic monomers comprise cationic monomers and anionic monomers.
  • the cationic monomers comprise acryloxyethyltrimethyl ammonium chloride, acryloxyethyltrimethyl benzyl ammonium chloride, methacryloxyethyltrimethyl ammonium chloride, methacryloxyethyltrimethyl p-toluenesulfonate, methacryloyloxyethyl dimethylbenzyl ammonium chloride, dimethylaminoethyl acrylate, t-butylaminoethyl methacrylate, vinyl imidazole or vinyl pyridine.
  • the anionic monomers comprise acrylic acid, methacrylic acid, itaconic acid, beta-carboxyethyl acrylate, maleic anhydride or sodium salt thereof.
  • the examples of the anionic monomers are sodium acrylate, sodium l-allyloxy-2hydroxypropane sulfonate, ammonium allylpolyethoxy sulfate, sodium styrene sulfonate or 2-acrylamido-2-methyl propane sulfonic acid.
  • the non-ionic monomers comprise hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, acrylamide, N-hydroxyethyl acrylamide or polyvinylpyrolidone.
  • the hydrophobic monomers comprise methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, t-butyl methacrylate, styrene or vinylidine fluoride. Additionally, although the monomers of acrylonitrile and methacrylonitrile are water soluble, the polymer made of these monomers are also used as the hydrophobic monomers.
  • the water-swellable polymer further reacts with a cross-linking agent to conduct a cross-linking reaction.
  • the cross-linking agent may cross-linked to the hydrophilic or hydrophobic groups of the water-swellable polymer (preferably to react with the hydrophilic groups) to reduce the solubility of the water-swellable polymer.
  • the cross-linking agent comprises acid anhydride, epoxy, isocyanate, aminoplast resins (the product of formaldehyde reacting with melamine, urea or guanamine), alkoxymethyl acrylamide, carbodiimide, aziridine or derivatives thereof.
  • the acid anhydride is cross-linked to a hydroxyl group of the water-swellable polymer.
  • the epoxy is cross-linked to a carboxyl group, a hydroxyl group, or an amine group of the water-swellable polymer.
  • the isocyanate is cross-linked to a hydroxyl group of the water- swellable polymer.
  • the aminoplast resins are cross-linked to a hydroxyl group, a carboxyl group or an amide group of the water-swellable polymer.
  • the alkoxymethyl acrylamide is cross-linked to a hydroxyl group of the water-swellable polymer.
  • the carbodiimide or aziridine is cross-linked to a carboxyl group of the water-swellable polymer.
  • the cross-linking reaction further comprises an ionic cross-linking reaction.
  • a multi-chlorinated hydrocarbon is cross-linked to an amine group of the water-swellable polymer to form a quaternary ammonium salt.
  • 1,6-dichlorohexane is cross-linked to an amine group of the water-swellable polymer to form a quaternary ammonium salt to complete a quaternization reaction for ionic crosslinking.
  • hydrophilic group of the water-swellable polymer may react with crosslinkable monomers, such as N-isobutoxymethyl acrylamide.
  • the water-swellable polymer may be made of a modified polymer, such as polyvinyl alcohol, carboxymethyl cellulose or hydroxyethyl cellulose.
  • the polyvinyl alcohol is the hydrolysis product of the polyvincylacetate, and the hydroxyethyl cellulose is an addition reaction product by reacting ethylene oxide with cellulose.
  • the fiber composite membrane is in the form of a fiber with a bonder, and the fiber is made from water-swellable polymer by spinning techniques, such as solution spinning or electro spinning. Then, the binder is filled in the fiber by coating or dipping. Finally, after a roller or plate process, a dense fiber composite membrane is obtained.
  • the binder may be a water-swellable polymer or other polymers, other polymers are such as polyvinyl alcohol (PVA), polystyrene (PS), polyacrylamides, polymethacrylamides, polymethacrylates, polyacrylates, polyester, hydroxyethyl cellulosic or hydroxypropyl cellulose.
  • PVA polyvinyl alcohol
  • PS polystyrene
  • polyacrylamides polymethacrylamides
  • polymethacrylates polymethacrylates
  • polyacrylates polyester, hydroxyethyl cellulosic or hydroxypropyl cellulose.
  • the function of the binder is to improve the mechanic strength of the filter materials and narrow the holes in the surface of desalination layer.
  • an additional cross-linking agent is added into the binder.
  • methylated melamine-formaldehyde resin such as hexamethoxymethylmelamine
  • methylated melamine-formaldehyde resin such as hexamethoxymethylmelamine
  • the fiber is made from the water-swellable polymer by electro spinning. Then, the binder of polyacrylonitrile (PAN) is added into the fiber to form the fiber composite membrane.
  • PAN polyacrylonitrile
  • the fiber is made from polyacrylonitrile (PAN) by electro spinning. Then, the binder of water-swellable polymer is added into the fiber to form the fiber composite membrane.
  • PAN polyacrylonitrile
  • the fiber is made from the water-swellable polymer by electro spinning. Then, the binder of water-swellable polymer is added into the fiber to form the fiber composite membrane.
  • the fiber of the fiber composite membrane of the invention comprises a microfiber or nanofiber, wherein the microfiber has a diameter of about 1-30 ⁇ , preferably 1-15 ⁇ , and the nanofiber has a diameter of about 10-1000 nm, preferably 50- 500 nm.
  • the conventional reverse osmosis (RO) membranes have smaller pores (smaller than 1 nm). Thus, the membranes must be operated under a pressure which is larger than about 500 psi, even 1000 psi.
  • the main advantage of the invention is that the filtration material of the invention can exhibit high flux as with the conventional RO membrane, but may be operated under a lower pressure environment. Flux of the filtration material of the invention is 18 L/m /hr, and salt rejection is 60 %-90 , when tested under an operation pressure smaller than 10 psi.
  • the open pores of the fiber composite membrane of the invention may be used as an effective desalination membrane, thus the filtration material of the invention may be operated under a lower pressure environment.
  • the filtration material of the invention is only made by one support layer with one desalination layer for desalination effect.
  • the filtration material may be additionally combined with other conventional permeable, semi-permeable membranes or other polymer films according to actual application.
  • the filtration material of the invention has a desalination effect, and the filtration material still has high flux even if operated under lower pressure.
  • the filtration material of the invention may be used in a desalination process, wastewater treatment, ultrapure water treatment, water softening or heavy metals recovery.
  • the filtration material of Comparative Example 1 is made by two support layers.
  • a bottom layer is polyester (PET) non- woven (purchased from HO YU TEXTILE CO., LTD) and an upper layer is polyacrylonitrile (PAN) (purchased from TONGHWA synthetic fiber CO. Ltd., molar weight of about 150,000-300,000).
  • PET polyester
  • PAN polyacrylonitrile
  • the desalination layer of Comparative Example 2 was fabricated as following. 30 g of polyacrylonitrile (PAN) was dissolved in 200 g of N, N-dimethyl-acetamide (DMAc) to provide a spinning solution. The nanofiber material was obtained by electro spinning with an applied voltage of 39 KV, spray amount of 1000 ⁇ / ⁇ , a 25 cm distance between the collector and spinneret, and air pressure of 2.8 kg/cm . A nanofiber material with a diameter of 280 nm-380 nm and weight of 30-60 g/m was obtained.
  • PAN polyacrylonitrile
  • DMAc N, N-dimethyl-acetamide
  • Example 1 fabrication of the water -swellable polymer
  • Example 2 36 g of the polymer of Example 1 was dissolved in 200 g of N, N-dimethyl- acetamide (DMAc) to provide a spinning solution.
  • the nanofiber material was obtained by electro spinning with an applied voltage of 39 KV, spray amount of 1200 ⁇ / ⁇ , a 20 cm distance between the collector and spinneret, and air pressure of 5 kg/cm .
  • PAN polyacrylonitrile
  • DMAc N, N-dimethyl- acetamide
  • the nanofiber material was obtained by electro spinning with an applied voltage of 39 KV, spray amount of 1000 ⁇ / ⁇ , a 25 cm distance between the collector and spinneret, and air pressure of 2.8 kg/cm .
  • a nanofiber material with a diameter of 280 nm-380 nm and weight of 30-60 g/m was obtained.
  • Example 4 The desalination layer of Example 4 was fabricated as following. 3 g of Example 1 (used as binder) was dissolved in 27 g alcohol, and then 2.6 g of 1,6- dichlorohexane (used as cross-linking agent) was added into the alcohol to form a mixture. Next, the mixture was coated on the nanofiber material of Example 2 at 70°C for 4 hours to form the fiber composite membrane.
  • Example 1 used as binder
  • 1,6- dichlorohexane used as cross-linking agent
  • Example 5 The desalination layer of Example 5 was fabricated as following. 0.6 g of Example 1 (used as binder) was dissolved in 29.4 g alcohol, and then 0.42 g of 1,6- dichlorohexane (used as cross-linking agent) was added into the alcohol to form a mixture.
  • 0.6 g of Example 1 (used as binder) was dissolved in 29.4 g alcohol, and then 0.42 g of 1,6- dichlorohexane (used as cross-linking agent) was added into the alcohol to form a mixture.
  • Example 6 The desalination layer of Example 6 was fabricated as following. 3 g of commercially available polystyrene (PS) (used as binder) was dissolved in 27 g p-xylene to form a mixture. Next, the mixture was coated on the nanofiber material of Example 2 at 70
  • Example 7 The desalination layer of Example 7 was fabricated as following. 3 g of Example 1 (used as binder) was dissolved in 27 g alcohol, and then 2.1 g of 1,6- dichlorohexane (used as cross-linking agent) was added into the alcohol to form a mixture. Next, the mixture was coated on the commercial available polypropylene (PP) nanofiber material at 70°C for 4 hours to form the fiber composite membrane.
  • PP polypropylene
  • the desalination layer of Example 8 was fabricated as following. 10 g of polyvinyl alcohol (PVA) (purchased from ChangChun Group) (used as binder) was dissolved in 90 g water, and then 0.01 g of maleic anhydride (MA) (used as cross-linking agent) was added into the water to form a mixture. Next, the mixture was coated on the nanofiber material of Example 3 at 70°C for 4 hours to form the fiber composite membrane.
  • PVA polyvinyl alcohol
  • MA maleic anhydride

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Organic Chemistry (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)

Abstract

Disclosed is a filtration material for desalination, including a support layer, and a desalination layer formed on the support layer, wherein the desalination layer is a fiber composite membrane and includes at least one water-swellable polymer. The water-swellable polymer is made of hydrophilic monomers and hydrophobic monomers, and the hydrophilic monomers comprise ionic monomers and non-ionic monomers, and the ionic monomers comprise cationic monomers and anionic monomers.

Description

FILTRATION MATERIAL FOR DESALINATION
BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The present invention relates to a filtration material for desalination, and in particular relates to a filtration material made of a water- swellable polymer.
Description of the Related Art
[0002] Currently, filtration materials for desalination which are applied to sea water, industrial water and wastewater, have been developed by various sources all around the world. Conventionally, design issues concern the efficient treatment of salt water, the reduction of operating pressure, low energy consumption, and reduction in the cost of water treatment.
[0003] US Patent No.4828700 discloses a membrane made of cross-linked poly methyl methacrylate. The membrane performance has a 9.1 GFD flux, and a 97.9 % salt rejection, when tested under an operation pressure of 400 psi using 2500 ppm of salt water. [0004] US Patent No.5755964 discloses a reverse osmosis (RO) membrane, wherein the RO membrane has good wetting property by using an amine compound to treat the surface of the RO membrane. The RO membrane performance has a 48 GFD flux, when tested under an operation pressure of 225 psi using 2000 ppm of salt water. The RO membrane exhibits high flux like nanofiltration material.
[0005] The filtration materials for desalination in prior art are made of nanoporous polymeric thin film. However, the nanoporous polymeric thin film must be operated under a high pressure. Alternatively, if the filtration materials are made of hydrophilic materials, the operation pressure may be decreased, which would thereby improve desalination efficiency.
BRIEF SUMMARY OF THE INVENTION
[0006] The present invention provides a filtration material for desalination, comprising: a support layer, and a desalination layer formed on the support layer, wherein the desalination layer is a fiber composite membrane and comprises at least one water- swellable polymer.
[0007] A detailed description is given in the following embodiments with reference to the accompanying drawings.
DETAILED DESCRIPTION OF THE INVENTION
[0008] The following description is of the best-contemplated mode of carrying out the invention. This description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. The scope of the invention is best determined by reference to the appended claims.
[0009] The invention provides a filtration material for desalination, which comprises a support layer and a desalination layer formed on the support layer. The support layer is used to support the desalination layer. The desalination layer is a fiber composite membrane and comprises at least one water- swellable polymer. The term "water-swellable polymer" means that the polymer can swell itself by absorbing water. Although the polymer absorbs a lot of water, the structure of the polymer is not deformed. In some cases, the water-swellable polymer is not a water soluble polymer and is made of hydrophilic monomers and hydrophobic monomers. Alternatively, the water-swellable polymer is a water soluble polymer, and it maintains the swellable property and reduces the hydrolysis property by an appropriate cross-linking reaction.
[0010] The support layer comprises one or more porous materials, wherein the porous materials comprise cellouse ester, poly sulf one, polyacrylonitrile (PAN), polyvinglidene fluoride (PVDF), polyetheretherketone (PEK), polyester (PET), polyimide (PI), chlorinated polyvinyl chloride (PVC) or styrene acrylnitrile (SAN). The support layer may be self- made or commercially available and may be in the form of non-woven, woven or open pores.
[0011] In one embodiment, the filtration material for desalination comprises two support layers in which a bottom layer is polyester (PET), and an upper layer is polyacrylonitrile (PAN) or polysulfone. The two support layers may be in the form of a non- woven or woven layer, and preferably non- woven layer.
[0012] The hydrophilic monomers of the water- swellable polymer comprise ionic monomers and non-ionic monomers.
[0013] The ionic monomers comprise cationic monomers and anionic monomers. The cationic monomers comprise acryloxyethyltrimethyl ammonium chloride, acryloxyethyltrimethyl benzyl ammonium chloride, methacryloxyethyltrimethyl ammonium chloride, methacryloxyethyltrimethyl p-toluenesulfonate, methacryloyloxyethyl dimethylbenzyl ammonium chloride, dimethylaminoethyl acrylate, t-butylaminoethyl methacrylate, vinyl imidazole or vinyl pyridine.
[0014] The anionic monomers comprise acrylic acid, methacrylic acid, itaconic acid, beta-carboxyethyl acrylate, maleic anhydride or sodium salt thereof. The examples of the anionic monomers are sodium acrylate, sodium l-allyloxy-2hydroxypropane sulfonate, ammonium allylpolyethoxy sulfate, sodium styrene sulfonate or 2-acrylamido-2-methyl propane sulfonic acid.
[0015] The non-ionic monomers comprise hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, acrylamide, N-hydroxyethyl acrylamide or polyvinylpyrolidone. [0016] The hydrophobic monomers comprise methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, t-butyl methacrylate, styrene or vinylidine fluoride. Additionally, although the monomers of acrylonitrile and methacrylonitrile are water soluble, the polymer made of these monomers are also used as the hydrophobic monomers.
[0017] In order to improve the mechanic strength of the fiber composite membrane, the water-swellable polymer further reacts with a cross-linking agent to conduct a cross-linking reaction. The cross-linking agent may cross-linked to the hydrophilic or hydrophobic groups of the water-swellable polymer (preferably to react with the hydrophilic groups) to reduce the solubility of the water-swellable polymer. The cross-linking agent comprises acid anhydride, epoxy, isocyanate, aminoplast resins (the product of formaldehyde reacting with melamine, urea or guanamine), alkoxymethyl acrylamide, carbodiimide, aziridine or derivatives thereof.
[0018] In one embodiment, the acid anhydride is cross-linked to a hydroxyl group of the water-swellable polymer. In another embodiment, the epoxy is cross-linked to a carboxyl group, a hydroxyl group, or an amine group of the water-swellable polymer. In yet another embodiment, the isocyanate is cross-linked to a hydroxyl group of the water- swellable polymer. In another embodiment, the aminoplast resins are cross-linked to a hydroxyl group, a carboxyl group or an amide group of the water-swellable polymer. In one embodiment, the alkoxymethyl acrylamide is cross-linked to a hydroxyl group of the water-swellable polymer. In yet another embodiment, the carbodiimide or aziridine is cross-linked to a carboxyl group of the water-swellable polymer.
[0019] In addition to the chemical cross-linking reaction, the cross-linking reaction further comprises an ionic cross-linking reaction. For example, a multi-chlorinated hydrocarbon is cross-linked to an amine group of the water-swellable polymer to form a quaternary ammonium salt. In one embodiment, 1,6-dichlorohexane is cross-linked to an amine group of the water-swellable polymer to form a quaternary ammonium salt to complete a quaternization reaction for ionic crosslinking.
[0020] Furthermore, the hydrophilic group of the water-swellable polymer may react with crosslinkable monomers, such as N-isobutoxymethyl acrylamide.
[0021] Moreover, the water-swellable polymer may be made of a modified polymer, such as polyvinyl alcohol, carboxymethyl cellulose or hydroxyethyl cellulose. The polyvinyl alcohol is the hydrolysis product of the polyvincylacetate, and the hydroxyethyl cellulose is an addition reaction product by reacting ethylene oxide with cellulose.
[0022] Additionally, the fiber composite membrane is in the form of a fiber with a bonder, and the fiber is made from water-swellable polymer by spinning techniques, such as solution spinning or electro spinning. Then, the binder is filled in the fiber by coating or dipping. Finally, after a roller or plate process, a dense fiber composite membrane is obtained.
[0023] The binder may be a water-swellable polymer or other polymers, other polymers are such as polyvinyl alcohol (PVA), polystyrene (PS), polyacrylamides, polymethacrylamides, polymethacrylates, polyacrylates, polyester, hydroxyethyl cellulosic or hydroxypropyl cellulose.
[0024] The function of the binder is to improve the mechanic strength of the filter materials and narrow the holes in the surface of desalination layer.
[0025] In order to reduce solubility of the fiber composite membrane and enhance the mechanical strength of fiber composite membrane, an additional cross-linking agent is added into the binder. For example, methylated melamine-formaldehyde resin (such as hexamethoxymethylmelamine) is added into the binder, and it is cross-linked to a hydroxyl group of the fiber composite membrane to change the solubility of the fiber composite membrane.
[0026] In one embodiment, the fiber is made from the water-swellable polymer by electro spinning. Then, the binder of polyacrylonitrile (PAN) is added into the fiber to form the fiber composite membrane.
[0027] In another embodiment, the fiber is made from polyacrylonitrile (PAN) by electro spinning. Then, the binder of water-swellable polymer is added into the fiber to form the fiber composite membrane.
[0028] In a preferably embodiment, the fiber is made from the water-swellable polymer by electro spinning. Then, the binder of water-swellable polymer is added into the fiber to form the fiber composite membrane.
[0029] The fiber of the fiber composite membrane of the invention comprises a microfiber or nanofiber, wherein the microfiber has a diameter of about 1-30 μιη, preferably 1-15 μιη, and the nanofiber has a diameter of about 10-1000 nm, preferably 50- 500 nm.
[0030] The conventional reverse osmosis (RO) membranes have smaller pores (smaller than 1 nm). Thus, the membranes must be operated under a pressure which is larger than about 500 psi, even 1000 psi. The main advantage of the invention is that the filtration material of the invention can exhibit high flux as with the conventional RO membrane, but may be operated under a lower pressure environment. Flux of the filtration material of the invention is 18 L/m /hr, and salt rejection is 60 %-90 , when tested under an operation pressure smaller than 10 psi.
[0031] Compared with prior art, the open pores of the fiber composite membrane of the invention may be used as an effective desalination membrane, thus the filtration material of the invention may be operated under a lower pressure environment. Note that the filtration material of the invention is only made by one support layer with one desalination layer for desalination effect. The filtration material may be additionally combined with other conventional permeable, semi-permeable membranes or other polymer films according to actual application.
[0032] Because the fiber composite membrane has the porous properties, the filtration material of the invention has a desalination effect, and the filtration material still has high flux even if operated under lower pressure. The filtration material of the invention may be used in a desalination process, wastewater treatment, ultrapure water treatment, water softening or heavy metals recovery.
[0033] [Example]
[0034] Comparative Example 1
[0035] The filtration material of Comparative Example 1 is made by two support layers. A bottom layer is polyester (PET) non- woven (purchased from HO YU TEXTILE CO., LTD) and an upper layer is polyacrylonitrile (PAN) (purchased from TONGHWA synthetic fiber CO. Ltd., molar weight of about 150,000-300,000).
[0036] Comparative Example 2
[0037] The support layer of Comparative Example 1 was used as the support layer of Example 2.
[0038] The desalination layer of Comparative Example 2 was fabricated as following. 30 g of polyacrylonitrile (PAN) was dissolved in 200 g of N, N-dimethyl-acetamide (DMAc) to provide a spinning solution. The nanofiber material was obtained by electro spinning with an applied voltage of 39 KV, spray amount of 1000 μί/ητίη, a 25 cm distance between the collector and spinneret, and air pressure of 2.8 kg/cm . A nanofiber material with a diameter of 280 nm-380 nm and weight of 30-60 g/m was obtained.
[0039] 3 g of polystyrene (PS) (purchased from Aldrich, used as binder) was dissolved in 27 g p-xylene to form a mixture. Next, the mixture was coated on the above nanofiber material at 70°C for 1 hours to form the fiber composite membrane.
[0040] Example 1 fabrication of the water -swellable polymer
[0041] 10 g of sodium styrenesulfate, 40 g of 4-vinyl pyridine, 7 g of styrene, 50 g of deionized water and 50 g of isopropanol (IPA) were dissolved in a reaction flask, and stirred under N2 atmosphere at 70°C. A solution containing 0.2 g of potassium persulfate
(KPS) in 10 mL of deionized water was slowly added into the reaction flask, and kept for 3 hours. The mixture was purified to obtain 50.1 g of the water- swellable polymer (88 %).
[0042] Example 2 fabrication of nanofiber materials
[0043] 36 g of the polymer of Example 1 was dissolved in 200 g of N, N-dimethyl- acetamide (DMAc) to provide a spinning solution. The nanofiber material was obtained by electro spinning with an applied voltage of 39 KV, spray amount of 1200 μΕ/ητίη, a 20 cm distance between the collector and spinneret, and air pressure of 5 kg/cm . A nanofiber material with a diameter of 70 nm-120 nm and weight of 60-94 g/m was obtained.
[0044] Example 3 fabrication of nanofiber composite materials
[0045] 30 g of polyacrylonitrile (PAN) was dissolved in 200 g of N, N-dimethyl- acetamide (DMAc) to provide a spinning solution. The nanofiber material was obtained by electro spinning with an applied voltage of 39 KV, spray amount of 1000 μΕ/ητίη, a 25 cm distance between the collector and spinneret, and air pressure of 2.8 kg/cm . A nanofiber material with a diameter of 280 nm-380 nm and weight of 30-60 g/m was obtained.
[0046] Example 4
[0047] The support layer of Comparative Example 1 was used as the support layer of Example 4.
[0048] The desalination layer of Example 4 was fabricated as following. 3 g of Example 1 (used as binder) was dissolved in 27 g alcohol, and then 2.6 g of 1,6- dichlorohexane (used as cross-linking agent) was added into the alcohol to form a mixture. Next, the mixture was coated on the nanofiber material of Example 2 at 70°C for 4 hours to form the fiber composite membrane.
[0049] Example 5
[0050] The support layer of Comparative Example 1 was used as the support layer of Example 5.
[0051] The desalination layer of Example 5 was fabricated as following. 0.6 g of Example 1 (used as binder) was dissolved in 29.4 g alcohol, and then 0.42 g of 1,6- dichlorohexane (used as cross-linking agent) was added into the alcohol to form a mixture.
Next, the mixture was coated on the nanofiber material of Example 3 at 70°C for 4 hours to form the fiber composite membrane.
[0052] Example 6
[0053] The support layer of Comparative Example 1 was used as the support layer of Example 6.
[0054] The desalination layer of Example 6 was fabricated as following. 3 g of commercially available polystyrene (PS) (used as binder) was dissolved in 27 g p-xylene to form a mixture. Next, the mixture was coated on the nanofiber material of Example 2 at 70
°C for 1 hour to form the fiber composite membrane. [0055] Example 7
[0056] The support layer of Comparative Example 1 was used as the support layer of Example 7.
[0057] The desalination layer of Example 7 was fabricated as following. 3 g of Example 1 (used as binder) was dissolved in 27 g alcohol, and then 2.1 g of 1,6- dichlorohexane (used as cross-linking agent) was added into the alcohol to form a mixture. Next, the mixture was coated on the commercial available polypropylene (PP) nanofiber material at 70°C for 4 hours to form the fiber composite membrane.
[0058] Example 8
[0059] The support layer of Comparative Example 1 was used as the support layer of Example 8.
[0060] The desalination layer of Example 8 was fabricated as following. 10 g of polyvinyl alcohol (PVA) (purchased from ChangChun Group) (used as binder) was dissolved in 90 g water, and then 0.01 g of maleic anhydride (MA) (used as cross-linking agent) was added into the water to form a mixture. Next, the mixture was coated on the nanofiber material of Example 3 at 70°C for 4 hours to form the fiber composite membrane.
[0061] The desalination efficiency of Comparative Example 1-2 and Example 4-8 are shown in Table 1. As shown in Table 1, the filtration material made by the water- swellable polymer of the invention had a good desalination effect, with desalination efficiency of about 50-95%.
[0062] Table 1
Example 1 Example 1
Examp le 5 PAN (commercial The polymer of 87.58 %
available) Example 1
Examp le 6 The polymer of PS (commercial 82.50%
Example 1 available)
Examp le 7 PP (commercial The polymer of 64.28 %
available) Example 1
Examp le 8 PAN (commercial PVA (commercial 65.04 %
available) available)
[0063] While the invention has been described by way of example and in terms of the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.

Claims

What is claimed is:
1. A filtration material for desalination, comprising: a support layer; and a desalination layer formed on the support layer, wherein the desalination layer is a fiber composite membrane and comprises at least one water- swellable polymer.
2. The filtration material for desalination as claimed in claim 1, wherein the support layer comprises one or more porous materials.
3. The filtration material for desalination as claimed in claim 1, wherein the fiber composite membrane is in the form of a fiber with a binder, and the fiber comprises microfiber or nanofiber.
4. The filtration material for desalination as claimed in claim 2, wherein the porous materials comprise cellouse ester, polysulfone, polyacrylonitrile (PAN), polyvinglidene fluoride (PVDF), polyetheretherketone (PEK), polyester (PET), polyimide (PI), chlorinated polyvinyl chloride (PVC) or styrene acrylnitrile (SAN).
5. The filtration material for desalination as claimed in claim 1, wherein the water-swellable polymer is made of hydrophilic monomers and hydrophobic monomers, and the hydrophilic monomers comprise ionic monomers and non-ionic monomers, and the ionic monomers comprise cationic monomers and anionic monomers.
6. The filtration material for desalination as claimed in claim 5, wherein the cationic monomers comprise acryloxyethyltrimethyl ammonium chloride,
acryloxyethyltrimethyl benzyl ammonium chloride, methacryloxyethyltrimethyl ammonium chloride, methacryloxyethyltrimethyl p-toluenesulfonate,
methacryloyloxyethyl dime thy lbenzyl ammonium chloride, dimethylaminoethyl acrylate, t-butylaminoethyl me thacrylate, vinyl imidazole or vinyl pyridine.
7. The filtration material for desalination as claimed in claim 5, wherein the anionic monomers comprise acrylic acid, methacrylic acid, itaconic acid, beta- carboxyethyl acrylate, maleic anhydride or sodium salt thereof.
8. The filtration material for desalination as claimed in claim 5, wherein the non- ionic monomers comprise hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, acrylamide, N-hydroxyethyl acrylamide or
polyvinylpyrolidone.
9. The filtration material for desalination as claimed in claim 5, wherein the hydrophobic monomers comprise methyl acrylate, ethyl acrylate, butyl acrylate, 2- ethylhexyl acrylate, methyl methacrylate, t-butyl methacrylate, styrene or vinylidine fluoride.
10. The filtration material for desalination as claimed in claim 1, wherein the water-swellable polymer further reacts with a cross-linking agent to conduct a cross- linking reaction.
11. The filtration material for desalination as claimed in claim 10, wherein the cross-linking agent comprises acid anhydride, epoxy, isocyanate, aminoplast resins, alkoxymethyl acrylamide, carbodiimide, aziridine or derivatives thereof.
12. The filtration material for desalination as claimed in claim 11, wherein the acid anhydride is cross-linked to a hydroxyl group of the water-swellable polymer.
13. The filtration material for desalination as claimed in claim 11, wherein the epoxy is cross-linked to a carboxyl group, a hydroxyl group, or an amine group of the water-swellable polymer.
14. The filtration material for desalination as claimed in claim 11, wherein the isocyanate is cross-linked to a hydroxyl group of the water-swellable polymer.
15. The filtration material for desalination as claimed in claim 11, wherein the aminoplast resins are cross-linked to a hydroxyl group, a carboxyl group or an amide group of the water-swellable polymer.
16. The filtration material for desalination as claimed in claim 11, wherein the alkoxymethyl acrylamide is cross-linked to a hydroxyl group of the water-swellable polymer.
17. The filtration material for desalination as claimed in claim 11, wherein the carbodiimide or aziridine is cross-linked to a carboxyl group of the water-swellable polymer.
18. The filtration material for desalination as claimed in claim 10, wherein the cross-linking reaction further comprises an ionic cross-linking reaction.
19. The filtration material for desalination as claimed in claim 18, wherein a multi-chlorinated hydrocarbon is cross-linked to an amine group of the water- swellable polymer to form a quaternary ammonium salt.
20. The filtration material for desalination as claimed in claim 1, wherein the water-swellable polymer comprises polyvinyl alcohol, carboxymethyl cellulose or hydroxy ethyl cellulose.
EP11821071.5A 2010-09-02 2011-07-27 FILTRATION MATERIAL FOR DESALINATION Withdrawn EP2611528A4 (en)

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CN103055715B (en) * 2013-02-04 2015-01-28 北京科泰兴达高新技术有限公司 Composite nanofiltration membrane and preparation method thereof
CA2919820C (en) * 2013-07-31 2022-07-19 Council Of Scientific & Industrial Research Anion exchange membrane for electrodialysis applications and process for the preparation thereof
US20160001235A1 (en) * 2014-07-07 2016-01-07 E I Du Pont De Nemours And Company Filtration membranes
CN104437433B (en) * 2014-11-28 2017-06-06 西北师范大学 A kind of preparation method of MethacryloyloxyethylTrimethyl Trimethyl Ammonium Chloride base anionic dye adsorbent
JP6534734B2 (en) * 2015-04-16 2019-06-26 株式会社クレハ Electrode structure and method of manufacturing the same
CN104906969B (en) * 2015-05-21 2017-03-01 浙江大学 Preparation method and application of cross-linked polyelectrolyte-surfactant complex
CN105289331B (en) * 2015-12-09 2017-11-17 苏州科技学院 Amphipathic triblock polymer PSxMAAy‑g‑fPEGzModified PVDF ultrafiltration membrane and preparation method thereof
CN105664742A (en) * 2016-04-13 2016-06-15 伊美特(上海)环保科技有限公司 Method for improving water flux and anti-pollution capacity of polyamide reverse osmosis membrane
CN112694758B (en) 2019-10-23 2022-05-24 财团法人工业技术研究院 Ion exchange resin composition, its preparation method and its formed membrane
CN111632580B (en) * 2020-05-18 2023-04-28 宁夏大学 A kind of polymer brush type magnetic graphene oxide adsorption material and preparation method thereof
CN112007514B (en) * 2020-07-28 2022-07-12 新长丰实业股份有限公司 Nanofiltration composite membrane
CN112108009B (en) * 2020-10-13 2022-04-22 上海希沃环境科技有限公司 Polytetrafluoroethylene membrane and hydrophilic treatment method and application thereof
US11642632B2 (en) 2020-11-13 2023-05-09 New Micropore, Inc. Nanofiltration composite membranes
CN112934002A (en) * 2021-02-19 2021-06-11 太原科技大学 Aziridine crosslinked sodium polyacrylate separation membrane and preparation method and application thereof
CN113244780B (en) * 2021-05-17 2022-02-08 江苏泷膜环境科技有限公司 Preparation method of anti-scaling and anti-yellowing composite reverse osmosis membrane
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US5084173A (en) * 1985-05-27 1992-01-28 Asahi Medical Co., Ltd. Hydrophilic composite porous membrane, a method of producing the plasma separator
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CN1263535C (en) * 2004-06-12 2006-07-12 国家海洋局杭州水处理技术研究开发中心 Polyamide reverse osmosis composite membrane and preparing method thereof
MX2007001821A (en) * 2004-08-13 2007-07-16 Univ Mcmaster Composite material comprising a non-crosslinked gel polymer.
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