WO1998007491A1 - Method and apparatus for extracting metal ions from aqueous solutions - Google Patents

Method and apparatus for extracting metal ions from aqueous solutions Download PDF

Info

Publication number
WO1998007491A1
WO1998007491A1 PCT/GB1997/002224 GB9702224W WO9807491A1 WO 1998007491 A1 WO1998007491 A1 WO 1998007491A1 GB 9702224 W GB9702224 W GB 9702224W WO 9807491 A1 WO9807491 A1 WO 9807491A1
Authority
WO
WIPO (PCT)
Prior art keywords
hollow fibre
fibre membranes
fibres
aqueous solution
compartment
Prior art date
Application number
PCT/GB1997/002224
Other languages
French (fr)
Inventor
Daniel Gilroy
Original Assignee
Ea Technology Limited
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 Ea Technology Limited filed Critical Ea Technology Limited
Publication of WO1998007491A1 publication Critical patent/WO1998007491A1/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/42—Electrodialysis; Electro-osmosis ; Electro-ultrafiltration; Membrane capacitive deionization
    • B01D61/422—Electrodialysis
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/42—Electrodialysis; Electro-osmosis ; Electro-ultrafiltration; Membrane capacitive deionization
    • B01D61/425—Electro-ultrafiltration
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/24—Dialysis ; Membrane extraction
    • B01D61/28—Apparatus therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/38—Liquid-membrane separation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D63/00—Apparatus in general for separation processes using semi-permeable membranes
    • B01D63/02—Hollow fibre modules
    • B01D63/04—Hollow fibre modules comprising multiple hollow fibre assemblies
    • B01D63/043—Hollow fibre modules comprising multiple hollow fibre assemblies with separate tube sheets
    • 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
    • C02F1/26—Treatment of water, waste water, or sewage by extraction
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2313/00—Details relating to membrane modules or apparatus
    • B01D2313/34—Energy carriers
    • B01D2313/345—Electrodes

Definitions

  • This invention relates to a method and apparatus for extracting metal ions from aqueous solutions.
  • the recovery of metals from aqueous waste streams is receiving increasing attention for two main reasons. Firstly, the metals may have intrinsic value, and secondly environmental legislation may preclude their discharge.
  • Methods exist for extracting metal ions from aqueous feed solutions by transferring them into an aqueous strip solution via an intermediate organic phase.
  • the organic and aqueous phases may be separated by membranes, or the organic phase may be actually supported in a single membrane. The latter situation is then referred to as a supported liquid membrane (SLM) .
  • SLM supported liquid membrane
  • the organic phase should contain the ligand, and a salt to provide electrical conductivity.
  • the membrane When working with a simple SLM system, the membrane may be prepared by soaking in the organic solution.
  • this technique will not produce a module which can be operated over an appreciable length of time, since the organic materials will eventually diffuse away into the aqueous streams.
  • a dual membrane arrangement is envisaged by the present invention, with organic phase circulation, to give continuous wetting or renewal of the organic content of the membranes as required.
  • a method of extracting metal ions from aqueous solutions which method comprises passing a feed aqueous solution containing said metal ions through the hollow cores of a first plurality of inert microporous hollow fibre membranes, said hollow fibre membranes being disposed in an electrically conducting organic liquid phase containing a ligand which is capable of combining with the said metal ions; passing a strip aqueous solution through the hollow cores of a second plurality of inert microporous hollow fibre membranes which is also disposed in said organic liquid phase; and applying an electrical potential between electrodes situated respectively in the said feed aqueous solution and said strip aqueous solution downstream of the respective pluralities of hollow fibre membranes so as to cause transfer of said metal ions from said feed solution to said ligand in said organic liquid phase and thereafter to said strip solution through the microporous walls of the respective pluralities of hollow fibre membranes.
  • the present invention also provides an apparatus for use in the above method which comprises
  • the electrodialysis apparatus and module described hereinafter is designed to overcome the above listed disadvantages. It is based on the use of hollow fibre membranes. Contactors based on such fibres are commercially available, but they contain single fibre bundles only. The present apparatus and device represents a significant advance over such contactors. The device is described with reference to Figure 1.
  • Two fibre bundles one for the feed aqueous solution (A, shown as black) , and one for the strip aqueous solution (B, shown as white) , are arranged for counter flow, as in Figure 1.
  • the aqueous streams flow along the hollow cores of the fibres of the bundles, with the organic phase on the outside.
  • the two bundles, A and B are intimately mixed, and the entry and exit ends of the fibres are terminated with resin seals 1-4, onto the cell body 5.
  • entry A and exit B for example are separated, to form an electrode compartment 6, which contains the cathode 7.
  • entry B and exit A are separated to form the anode compartment 8 , containing the anode 9.
  • the feed stream enters the apparatus at the inlet 10, passes along the cores of the fibres A, and exits at the outlet 11.
  • the strip stream enters the apparatus at the inlet 12, passes along the cores of the fibres B, and exits at the outlet 13.
  • the organic phase, which surrounds the fibres on the outside, may be circulated through the ports 14 and 15.
  • Fibres suitable for this application should be microporous, with pores of ⁇ 0.1 ⁇ m diameter, and with typical external and internal diameters of 300 and 250 ⁇ m, respectively.
  • the enhancement of area between the aqueous and organic phases depends on the number of fibres in the bundle, the packing density, and the fibre length. These parameters can be adjusted to suit the requirements.
  • the fibres should be of material which is inert to all the solutions or phases involved; polypropylene is an appropriate material for many applications.
  • the electrodes should be situated at the exit ends of the fibre bundles, so that any evolved gases are swept out of the apparatus, rather than into the centres of the fibres. Normally the anode, situated in the feed stream, would evolve oxygen. Precious metals, such as platinum, may be used for this purpose, as is well known.
  • the transferred metal can be collected by electrodeposition on the cathode, which may be of stainless steel or other inert material.
  • an excess pressure which is preferably a slight excess pressure may be applied on the aqueous side.
  • the organic solvent may be chosen by considering factors such as miscibility with water, ability to form conducting solutions, compatibility with materials of construction, and environmental constraints.
  • the salt added for purposes of conductivity should be insoluble in water.
  • the ligand should also be insoluble in water, but could be chosen to be specific to a given metal ion, so that this metal could be selectively extracted from the feed stream.
  • the apparatus would be run in batch recycle mode with each stream circulated through a holding tank by pumps. This arrangement enhances mass transfer to the membranes and electrodes. Metal may be removed from the cathode by mechanical means, or by dissolution.

Abstract

A method of extracting metal ions from aqueous solutions comprises passing a feed aqueous solution (10) containing said metal ions through the hollow cores of a first plurality (A) of inert microporous hollow fibre membranes, said hollow fibre membranes being disposed in an electrically conducting organic liquid phase (14) containing a ligand which is capable of combining with the said metal ions; passing a strip aqueous solution (12) through the hollow cores of a second plurality (B) of inert microporous hollow fibre membranes which is also disposed in said organic liquid phase; applying an electrical potential between electrodes (7, 9) situated respectively in the said feed aqueous solution and said strip aqueous solution downstream of the respective pluralities of hollow fibre membranes so as to cause transfer of said metal ions from said feed solution to said ligand in said organic liquid phase and thereafter to said strip solution through the microporous walls of the respective pluralities of hollow fibre membranes. An apparatus for performing the method is described.

Description

METHOD AND APPARATUS FOR EXTRACTING METAL IONS FROM AQUEOUS SOLUTIONS
This invention relates to a method and apparatus for extracting metal ions from aqueous solutions.
The recovery of metals from aqueous waste streams is receiving increasing attention for two main reasons. Firstly, the metals may have intrinsic value, and secondly environmental legislation may preclude their discharge.
Methods exist for extracting metal ions from aqueous feed solutions by transferring them into an aqueous strip solution via an intermediate organic phase.
In classical solvent extraction, for example, the separation of a metal ion M2+ occurs through the reaction:
M2+(w) + LH2(o) → 2H*(w) + ML(o) feed followed by
ML(o) + 2H*(w) → LH2(o) + M2+(w) strip where LH2 represents the acid form of the ligand used to assist the transfer, and (w) and (o) refer to the aqueous and organic phases, respectively. Hence, the ion is taken into, and then out of the organic phase, from the feed stream into the strip stream, and the driving force of the process is the transfer of the proton, H+, in the opposite direction.
Alternatively, in what is termed "electroassisted" extraction, the driving force is provided by applying an electrical potential across the interfaces, and the reactions become:
M2+(w) + L(o) → ML2+(o) feed and ML * (o) → L (o) + M2+ (w) strip
In a practical electrodialysis module, the organic and aqueous phases may be separated by membranes, or the organic phase may be actually supported in a single membrane. The latter situation is then referred to as a supported liquid membrane (SLM) . In either case, the organic phase should contain the ligand, and a salt to provide electrical conductivity.
When working with a simple SLM system, the membrane may be prepared by soaking in the organic solution. However, this technique will not produce a module which can be operated over an appreciable length of time, since the organic materials will eventually diffuse away into the aqueous streams. To overcome this problem, a dual membrane arrangement is envisaged by the present invention, with organic phase circulation, to give continuous wetting or renewal of the organic content of the membranes as required.
In previous work by the inventor of the present application the following electrodialysis experiments were performed.
(a) Copper was transferred between two separated aqueous solutions which were positioned above a relatively dense organic solvent (dichloroethane) . The latter contained dissolved salt (tetrabutylammonium tetraphenylborate) and ligand. An anode was located within the feed solution, and a cathode within the strip solution. The liquids were static, and the system was membrane free.
(b) A similar experiment was carried out with flowing solutions, using microporous membranes to separate the aqueous and organic phases. Copper was again transferred when current was applied. The results obtained highlighted the disadvantages of the simple arrangements used, namely
(1) The rate of transfer of copper increased initially as the current was increased, but then declined towards zero with further increases of current. In other words, there was an optimum current. The current density, however, was very low.
(2) The cell voltages were high because the current paths through the organic phase were relatively long, and this phase has low conductivity.
(3) It was difficult to prevent leakage of the organic phase, especially with vertical membranes in simple systems.
According to the present invention there is provided a method of extracting metal ions from aqueous solutions which method comprises passing a feed aqueous solution containing said metal ions through the hollow cores of a first plurality of inert microporous hollow fibre membranes, said hollow fibre membranes being disposed in an electrically conducting organic liquid phase containing a ligand which is capable of combining with the said metal ions; passing a strip aqueous solution through the hollow cores of a second plurality of inert microporous hollow fibre membranes which is also disposed in said organic liquid phase; and applying an electrical potential between electrodes situated respectively in the said feed aqueous solution and said strip aqueous solution downstream of the respective pluralities of hollow fibre membranes so as to cause transfer of said metal ions from said feed solution to said ligand in said organic liquid phase and thereafter to said strip solution through the microporous walls of the respective pluralities of hollow fibre membranes. The present invention also provides an apparatus for use in the above method which comprises
(a) an organic phase compartment which is adapted to have circulated therethrough an electrically conducting organic liquid containing a ligand;
(b) an anode compartment adjacent said organic phase compartment and provided with an anode and with an outlet for extracted feed aqueous metal solution;
(c) a cathode compartment adjacent said organic phase compartment and provided with a cathode and with an outlet for the strip aqueous solution;
(d) a first plurality of inert microporous hollow fibre membranes passing through said cathode compartment and said organic phase compartment and communicating with said anode compartment; said first plurality of hollow fibre membranes being adapted to be supplied to their hollow cores with feed aqueous solution before the fibres enter the cathode compartment;
(e) a second plurality of inert microporous hollow fibre membranes passing through said anode compartment and said organic phase compartment and communicating with said cathode compartment, said second plurality of the hollow fibre membranes being adapted to be supplied to their hollow cores with strip aqueous solution before the fibres enter the anode compartment; and
(f) means for applying an electrical potential to the said anode and cathode.
The electrodialysis apparatus and module described hereinafter is designed to overcome the above listed disadvantages. It is based on the use of hollow fibre membranes. Contactors based on such fibres are commercially available, but they contain single fibre bundles only. The present apparatus and device represents a significant advance over such contactors. The device is described with reference to Figure 1.
Two fibre bundles, one for the feed aqueous solution (A, shown as black) , and one for the strip aqueous solution (B, shown as white) , are arranged for counter flow, as in Figure 1. The aqueous streams flow along the hollow cores of the fibres of the bundles, with the organic phase on the outside. The two bundles, A and B, are intimately mixed, and the entry and exit ends of the fibres are terminated with resin seals 1-4, onto the cell body 5. Thus entry A and exit B, for example are separated, to form an electrode compartment 6, which contains the cathode 7. Similarly, entry B and exit A are separated to form the anode compartment 8 , containing the anode 9. The feed stream enters the apparatus at the inlet 10, passes along the cores of the fibres A, and exits at the outlet 11. The strip stream enters the apparatus at the inlet 12, passes along the cores of the fibres B, and exits at the outlet 13. The organic phase, which surrounds the fibres on the outside, may be circulated through the ports 14 and 15.
Important features of this invention are as follows:- (1) Fibres suitable for this application should be microporous, with pores of < 0.1 μm diameter, and with typical external and internal diameters of 300 and 250 μm, respectively. The enhancement of area between the aqueous and organic phases depends on the number of fibres in the bundle, the packing density, and the fibre length. These parameters can be adjusted to suit the requirements. The fibres should be of material which is inert to all the solutions or phases involved; polypropylene is an appropriate material for many applications. (2) The electrodes should be situated at the exit ends of the fibre bundles, so that any evolved gases are swept out of the apparatus, rather than into the centres of the fibres. Normally the anode, situated in the feed stream, would evolve oxygen. Precious metals, such as platinum, may be used for this purpose, as is well known. The transferred metal can be collected by electrodeposition on the cathode, which may be of stainless steel or other inert material.
(3) Since the fibre bundles are mixed together, the current paths through the organic phase between fibres A and B are very short. Ideally each fibre should be surrounded by 6 fibres from the opposite bundle in a close packed array. However, this coordination is impossible to achieve. The best arrangement is a regular array in which a fibre has 4 nearest neighbours of the opposite kind. In practice this would be difficult to realise, but a random well mixed array has a mean coordination number, of fibres of the opposite kind, of about 3.5, so that little is lost by a construction based on this premise.
(4) To prevent cross mixing through the micro-pores an excess pressure which is preferably a slight excess pressure may be applied on the aqueous side.
(5) The organic solvent may be chosen by considering factors such as miscibility with water, ability to form conducting solutions, compatibility with materials of construction, and environmental constraints. The salt added for purposes of conductivity should be insoluble in water. The ligand should also be insoluble in water, but could be chosen to be specific to a given metal ion, so that this metal could be selectively extracted from the feed stream. (6) The apparatus would be run in batch recycle mode with each stream circulated through a holding tank by pumps. This arrangement enhances mass transfer to the membranes and electrodes. Metal may be removed from the cathode by mechanical means, or by dissolution.

Claims

CL IMS :
1. A method of extracting metal ions from aqueous solutions which method comprises passing a feed aqueous solution containing said metal ions through the hollow cores of a first plurality of inert microporous hollow fibre membranes, said hollow fibre membranes being disposed in an electrically conducting organic liquid phase containing a ligand which is capable of combining with the said metal ions; passing a strip aqueous solution through the hollow cores of a second plurality of inert microporous hollow fibre membranes which is also disposed in said organic liquid phase; applying an electrical potential between electrodes situated respectively in the said feed aqueous solution and said strip aqueous solution downstream of the respective pluralities of hollow fibre membranes so as to cause transfer of said metal ions from said feed solution to said ligand in said organic liquid phase and thereafter to said strip solution through the microporous walls of the respective pluralities of hollow fibre membranes.
2. A method as claimed in claim 1 wherein the pluralities of hollow fibre membranes are arranged substantially parallel and in close proximity so that each hollow fibre of one plurality of fibres is close to several individual fibres of the other plurality of fibres.
3. A method as claimed in claim 1 or claim 2 wherein a slight excess pressure is applied to one or both of the aqueous solutions.
4. A method as claimed in any one of the preceding claims wherein the flows of feed aqueous solution and strip aqueous solution through their respective pluralities of hollow fibre membranes are in opposing directions.
5. A method as claimed in any one of the preceding claims wherein the organic liquid is made electrically conducting by a conducting salt dissolved in the organic liquid.
6. An apparatus for extracting metal ions from aqueous solutions by the method claimed in claim 1 which apparatus comprises
(a) an organic phase compartment which is adapted to have circulated therethrough an electrically conducting organic liquid containing a ligand;
(b) an anode compartment adjacent said organic phase compartment and provided with an anode and with an outlet for feed extracted aqueous metal solution;
(c) a cathode compartment adjacent said organic phase compartment and provided with a cathode and with an outlet for the strip aqueous solution;
(d) a first plurality of inert microporous hollow fibre membranes passing through said cathode compartment and said organic phase compartment and communicating with said anode compartment; said first plurality of hollow fibre membranes being adapted to be supplied to their hollow cores with feed aqueous solution before the fibres enter the cathode compartment;
(e) a second plurality of inert microporous hollow fibre membranes passing through said anode compartment and said organic phase compartment and communicating with said cathode compartment, said second plurality of the hollow fibre membranes being adapted to be supplied to their hollow cores with strip aqueous solution before the fibres enter the anode compartment; and
(f) means for applying an electrical potential to the said anode and cathode.
7. An apparatus as claimed in claim 6 wherein the pluralities of hollow fibre membranes are arranged substantially parallel and in close proximity so that each hollow fibre of one plurality of fibres is close to several individual fibres of the other plurality of fibres.
8. An apparatus as claimed in claim 6 or claim 7 wherein the walls of each fibre have pores of diameter less than 0.1 μm and wherein the external and internal diameters of the fibres are about 300 μ and 250 μm respectively.
9. An apparatus as claimed in any one of claims 6 to
8 wherein the fibres are made of polypropylene.
10. An apparatus as claimed in any one of claims 6 to
9 also comprising pump means for circulating the feed and strip aqueous solutions and the organic liquid through the apparatus from and to holding tanks.
PCT/GB1997/002224 1996-08-22 1997-08-19 Method and apparatus for extracting metal ions from aqueous solutions WO1998007491A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB9617586.4 1996-08-22
GBGB9617586.4A GB9617586D0 (en) 1996-08-22 1996-08-22 Method and apparatus for extracting metal ions from aqueous solutions

Publications (1)

Publication Number Publication Date
WO1998007491A1 true WO1998007491A1 (en) 1998-02-26

Family

ID=10798804

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1997/002224 WO1998007491A1 (en) 1996-08-22 1997-08-19 Method and apparatus for extracting metal ions from aqueous solutions

Country Status (2)

Country Link
GB (1) GB9617586D0 (en)
WO (1) WO1998007491A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2113297A1 (en) * 2008-04-30 2009-11-04 Celgard LLC A contained liquid membrane contactor and a method of manufacturing the same

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU1279650A1 (en) * 1985-02-06 1986-12-30 Одесский технологический институт пищевой промышленности им.М.В.Ломоносова Method of liquid extraction and reextraction of rubidium,vanadium and strontium salts
US4750918A (en) * 1985-05-28 1988-06-14 The Trustees Of The Stevens Institute Of Technology Selective-permeation gas-separation process and apparatus
US4789468A (en) * 1984-08-28 1988-12-06 The Trustees Of The Stevens Institute Of Technology Immobilized-interface solute-transfer apparatus
US4921612A (en) * 1985-10-22 1990-05-01 The Trustees Of Stevens Institute Of Technology Asymmetrically-wettable porous membrane process
JPH0768135A (en) * 1993-09-02 1995-03-14 Mitsubishi Rayon Co Ltd Electrodialysis method
RU2033441C1 (en) * 1991-11-21 1995-04-20 Институт химии и технологии редких элементов и минерального сырья Кольского научного центра РАН Method of metal reextraction from organic phase

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4789468A (en) * 1984-08-28 1988-12-06 The Trustees Of The Stevens Institute Of Technology Immobilized-interface solute-transfer apparatus
SU1279650A1 (en) * 1985-02-06 1986-12-30 Одесский технологический институт пищевой промышленности им.М.В.Ломоносова Method of liquid extraction and reextraction of rubidium,vanadium and strontium salts
US4750918A (en) * 1985-05-28 1988-06-14 The Trustees Of The Stevens Institute Of Technology Selective-permeation gas-separation process and apparatus
US4921612A (en) * 1985-10-22 1990-05-01 The Trustees Of Stevens Institute Of Technology Asymmetrically-wettable porous membrane process
RU2033441C1 (en) * 1991-11-21 1995-04-20 Институт химии и технологии редких элементов и минерального сырья Кольского научного центра РАН Method of metal reextraction from organic phase
JPH0768135A (en) * 1993-09-02 1995-03-14 Mitsubishi Rayon Co Ltd Electrodialysis method

Non-Patent Citations (10)

* Cited by examiner, † Cited by third party
Title
CHEMICAL ABSTRACTS, vol. 106, no. 18, 4 May 1987, Columbus, Ohio, US; abstract no. 140437, XP002049256 *
CHEMICAL ABSTRACTS, vol. 123, no. 4, 24 July 1995, Columbus, Ohio, US; abstract no. 37615, SCHIFFRIN, D.J.: "Electroassisted separation of metals by solvent extraction and supported liquid membranes" XP002049205 *
DATABASE WPI Section Ch Week 8734, Derwent World Patents Index; Class E14, AN 87-240549, XP002049206 *
DATABASE WPI Section Ch Week 9519, Derwent World Patents Index; Class A88, AN 95-144002, XP002049257 *
DATABASE WPI Section Ch Week 9551, Derwent World Patents Index; Class J01, AN 95-402369, XP002049207 *
EYAL A M ET AL: "INDUSTRIAL SEPARATION OF CARBOXYLIC AND AMINO ACIDS BY LIQUID MEMBRANES: APPLICABILITY, PROCESS CONSIDERATIONS, AND POTENTIAL ADVANTAGES", BIOTECHNOLOGY AND BIOENGINEERING INCLUDING: SYMPOSIUM BIOTECHNOLOGY IN ENERGY PRODUCTION AND CONSERVATION, vol. 41, no. 3, 5 February 1993 (1993-02-05), pages 287 - 295, XP000330645 *
HYDROMETALL. '94, PAP. INT. SYMP., 1994, LONDON, UK, pages 655 - 673 *
KISLIK V S ET AL: "HYBRID LIQUID MEMBRANE (HLM) AND SUPPORTED LIQUID MEMBRANE (SLM) BASED TRANSPORT OF TITANIUM (IV)", JOURNAL OF MEMBRANE SCIENCE, vol. 111, no. 2, 20 March 1996 (1996-03-20), pages 273 - 281, XP000638349 *
PATENT ABSTRACTS OF JAPAN vol. 095, no. 006 31 July 1995 (1995-07-31) *
YOSHINOBU SATO ET AL: "A NOVEL MEMBRANE EXTRACTOR USING HOLLOW FIBERS FOR SEPARATION AND ENRICHMENT OF METAL", JOURNAL OF CHEMICAL ENGINEERING OF JAPAN, vol. 23, no. 1, 1 February 1990 (1990-02-01), pages 23 - 29, XP000164801 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2113297A1 (en) * 2008-04-30 2009-11-04 Celgard LLC A contained liquid membrane contactor and a method of manufacturing the same
US7803274B2 (en) 2008-04-30 2010-09-28 Celgard Llc Contained liquid membrane contactor and a method of manufacturing the same

Also Published As

Publication number Publication date
GB9617586D0 (en) 1996-10-02

Similar Documents

Publication Publication Date Title
US5766438A (en) Electrolyzer and a method of operating the same
KR101433776B1 (en) Recycling of suppressor regenerants
KR102016503B1 (en) Desalting and power generating hybrid device and method
CN101898090B (en) Electrodeionization method and device with hydrodynamic flow splitting
EP1069079B1 (en) Electric deionization apparatus
US20210253452A1 (en) Electrochemical flow reactor
Sadyrbaeva RECOVERY OF COBALT (II) BY THE HYBRID LIQUID MEMBRANE− ELECTRODIALYSIS− ELECTROLYSIS PROCESS
US3827961A (en) Method for purifying ionically conducting solutions
WO1993023150A1 (en) Liquid extraction of aqueous solutions
Fels Recycle of dialysate from the artificial kidney by electrochemical degradatian of waste metabolites: Small-scale laboratory investigations
WO1998007491A1 (en) Method and apparatus for extracting metal ions from aqueous solutions
JPH10272474A (en) Electric deionization device
US4773979A (en) Equipment for purifying gases and liquids
WO2020036676A1 (en) Production of chemical products using electrochemical flow systems and slug flow and associated methods
JP3493242B2 (en) Method and apparatus for electrochemical recovery of nitrate
Franken Bipolar membrane technology and its applications
GB2396625A (en) Removal of an acid
US4525259A (en) Method and apparatus for electrodialysis
US11872528B2 (en) System and method for separating solvent from a fluid
US6051112A (en) Extraction method and apparatus
JPS5820289A (en) Device for changing concentration of salt in liquid
RU2800815C2 (en) Electrochemical flow reactor
JPWO2020028949A5 (en)
Stankovic Metal removal from effluents by electrowinning and a new design concept in wastewater purification technology
Nishikawa et al. Enrichment and volume reduction of tritiated water using electrolysis cell having hydrogen permeable cathode

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE

121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: JP

Ref document number: 98510507

Format of ref document f/p: F

122 Ep: pct application non-entry in european phase