US2723229A - Electrolytic process for the separation of ions of amphoteric and non-amphoteric metals - Google Patents

Electrolytic process for the separation of ions of amphoteric and non-amphoteric metals Download PDF

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Publication number
US2723229A
US2723229A US325686A US32568652A US2723229A US 2723229 A US2723229 A US 2723229A US 325686 A US325686 A US 325686A US 32568652 A US32568652 A US 32568652A US 2723229 A US2723229 A US 2723229A
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United States
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ions
compartment
amphoteric
aqueous solution
metals
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Expired - Lifetime
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US325686A
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English (en)
Inventor
George W Bodamer
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Rohm and Haas Co
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Rohm and Haas Co
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Priority to BE524792D priority Critical patent/BE524792A/xx
Priority to DENDAT1071669D priority patent/DE1071669B/de
Priority to NL82830D priority patent/NL82830C/xx
Application filed by Rohm and Haas Co filed Critical Rohm and Haas Co
Priority to US325686A priority patent/US2723229A/en
Priority to GB32978/53A priority patent/GB757928A/en
Priority to CH327709D priority patent/CH327709A/fr
Priority to FR1089388D priority patent/FR1089388A/fr
Application granted granted Critical
Publication of US2723229A publication Critical patent/US2723229A/en
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    • 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
    • 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
    • B01D71/76—Macromolecular material not specifically provided for in a single one of groups B01D71/08 - B01D71/74
    • B01D71/82—Macromolecular material not specifically provided for in a single one of groups B01D71/08 - B01D71/74 characterised by the presence of specified groups, e.g. introduced by chemical after-treatment

Definitions

  • This invention relates to an electrolytic process for the separation of ions of certain amphoteric and nonamphoteric metals. It relates to a method of electrolytically separating salts of certain non-amphoteric metals from salts of some amphoteric metals.
  • An object of this invention is to remove compounds of a non-amphoteric metal from mixtures containing compounds, usually salts, of both amphoteric and nonamphoteric metals. Another object is to provide a process for removing contaminating amphoteric compounds from aqueous solutions of salts of non-ampheteric metals or vice versa. A specific object is to remove ions of sodium from an aqueous solution containing both sodium and zinc ions.
  • the electrolytic process of this invention which comprises passing a direct electric current through an electrolysis cell which has an anode compartment containing hydrogen ions, a cathode compartment containing hydroxyl ions, and a third and intermediate compartment containing ions of both an amphoteric metal and a non-amphoteric metal, the partition between the anode compartment and the intermediate compartment being an anionic permselective diaphragm and the partition between the cathode compartment and the intermediate compartment being a cationic permselective diaphragm. Under these conditions the ions of the non-amphoteric metal migrate from the intermediate compartment into the cathode compartment while the ions of the amphoteric metal remain in the intermediate compartment.
  • the numeral 1 identifies a container which is divided into three compartments 6, 7 and 8 by an anionic permselective diaphragm 2, which is adjacent to the anode 4, and by a cationic permselective diaphragm 3, which is adjacent to the cathode 5.
  • the ionic-permselective diaphragms are described in greater detail below. Compartment 6 is the anode compartment because it contains anode 4 while compartment 7 is the cathode compartment because it contains the cathode 5.
  • the numeral 8 identifies the third and intermediate compartment into which is placed the solution containing the ions of the amphoteri'c and non-amphoteric metals to be separated.
  • the electrodes 4 When the cell is in operation, the electrodes 4 and are connected to a source of electric power not shown.
  • an aqueous solution of an acid preferably sulfuric acid
  • an aqueous solution of a strong base such as an. hydroxide of an. alkali metal, preferably sodium hydroxide
  • an aqueous solution of the ionizable compoundsordinarily salts of the amphoteric and non-amphoteric metals is placed in compartment 8.
  • a direct current is passed through the cell the ions in all of the compartments tend to migrate to the electrode of opposite charge.
  • ions of the non-amphoteric metal migrate from the intermediate compartment 8 through the cationic permselective membrane 3 into the cathode compartment where hydrogen is liberated and hydroxyl ions are formed.
  • the anions of the salts in the intermediate compartment are chloride ions, they are discharged at the anode and gaseous chlorine is liberated.
  • the hydroxyl ions in the cathode compartment tend to migrate to the anode but they are constrained by the cationic diaphragm 3.
  • hydrogen ions in the anode compartment tend to migrate to the cathode but are constrained by the anionic permselective diaphragm 2.
  • the ions of the amphoteric metal in the intermediate compartment do not migrate in any substantial amount through the cationic permselective diaphragm 3, as they would normally be expected to do.
  • the positive ions of the amphoteric metal are converted to negative ions, for example, zincate ions, on coming in contact with hydroxyl ions which have diffused to a slight extent into membrane 3.
  • the negative ions of the amphoteric metal then migrate in the opposite direction toward the anode but do not enter the anode compartment 6 because apparently they are reconverted to cations on coming in contact with hydrogen ions which have diffused to a limited extent into the anionic permselective diaphragm 2.
  • the facts here are independent of the theory and the net result in any case is that the ions of the amphoteric metal remain in the intermediate compartment in substantially quantitative amounts as the electrolysis proceeds.
  • the process provides a means of separating ions of certain amphoteric metals from ions of non-amphoteric metals.
  • sodium hydroxide is produced which contains so little zinc--if any -that it can be used with complete satisfaction in the viscose process.
  • the cell which is employed in the process of this invention can be varied as to size, closures, kinds of electrodes, construction materials, controls, siZe of the individual compartments, means for supplying aqueous solutions to the various compartments, means for removing the aqueous solutions from the compartments, embellishments, et cetera. What is essential, however, is that the cell have three compartments, one containing an anode, another containing a cathode and a third intermediate compartment which is separated from the anode compartment by means of an anionic permselective mem brane and is separated from the cathode compartment by means of a cationic permselective membrane.
  • the permselective membranes which divide the electrolysis cell into the three compartments are all important to the success of this process. They function by allowing only one kind of ions, either anions or cations, to pass through them while at the same time preventing-or at least restrainingthe passage of the other kind of ions through them from one compartment to another.
  • the anionic membrane contains an anion-exchange resin and the cationic membrane contains a cation-exchange resin.
  • the composition of the ionic permselective membranes can vary within reasonable limits but it is essential to this invention that the membranes contain enough resin so as to have suitably high conductance when employed in an electrolysis cell.
  • the permselective films which have proven to be most suitable for use in this process are those made by incorporating particles of ion-exchange resin in a film-forming matrix such as polyethylene, polyvinyl chloride, natural or synthetic rubber. Such films are the subject of my applications, Serial Nos. 202,577 and 205,413 (now Patents Nos. 2,681,320 and 2,681,319 respectively), to which reference is made, and they contain from 25% to 75% of the ion-exchange resins on a weight basis.
  • permselective films are known such as those based on cellophane or collodion; but those do not contain ion-exchange resins and are not recommended for use in the instant invention because they are not sufficiently chemicalresistant.
  • cation-exchange resins are well known and are widely used in the removal of ions from fluids. Suitable cation-exchange resins are described in U. 5. Patents Nos. 2,184,943; 2,195,196; 2,204,539; 2,228,159; 2,228,160; 2,230,641; 2,259,455; 2,285,750; 2,319,359; 2,366,007; 2,340,110; and 2,340,111. Some of the resins can be cast or otherwise produced in the form of free sheets or membranes.
  • the resins can be made on a porous support such as a piece of cloth or plastic screening.
  • cationic permselective membranes which have been employed, the ones which are preferred are those containing a sulfonated copolymer of styrene and divinylbenzene.
  • Suitable anion-exchange resins are described in U. S. Patents Nos. 2,106,486; 2,151,883; 2,223,930; 2,251,234; 2,259,169; 2,285,750; 2,341,907; 2,354,671; 2,354,672; 2,356,151; 2,366,008; 2,388,235; 2,402,384; 2,591,573; and 2,591,574.
  • membrane, film, sheet, layer, pellicle and diaphragm are used synonymously herein to describe the barriers or partitions between the compartments in the electrolysis cell.
  • the barriers are usually thin-of the order of thickness of 20 to 100 milsalthough thicker membranes have been used successfully.
  • the electric current is direct.
  • the current density can, of course, be varied and just what current density is maintained depends upon the construction of the cell and on other prevailing conditions of operation.
  • Current densities from 50 to 150 amperes per square foot of area of either permselective membrane have, however, been employed very successfully.
  • Example A cell equipped with platinum electrodes and similar to that in the drawing, was used.
  • the anolyte was a 10% aqueous solution of sulfuric acid while the catholyte was a 4% aqueous solution of sodium hydroxide.
  • Into the center compartment was charged an aqueous solution containing 26.8% sodium sulfate and 0.66% Zinc sulfate.
  • the anionic permselective membrane was composed of of an anion-exchange resin dispersed uniformly and intimately in a matrix of polyethylene and the cationic permselective membrane contained of a cation-exchange resin also dispersed in polyethylene.
  • the anion-exchange resin itself was of the strongly basic quaternary ammonium type made by chloromethylating a copolymer of 96% styrene and 4% divinylbenzene and reacting the chloromethylated product with trimethylamine according to the process of U. S. Patent No. 2,591,573.
  • the cation-exchange resin itself was a sulfonated cross-linked copolymer of styrene and divinylbenzene made by the process of U. S. Patent No. 2,366,007.
  • the anionic membrane was mounted adjacent to the anode while the cationic membrane was mounted adjacent to the cathode.
  • a direct current was passed through the cell for five hours and fifty minutes at a median current density of amperes per square foot.
  • the contents of the three compartments were removed and analyzed. It was found that 89% of the sodium sulfate, originally in the center compartment, had been converted into sodium hydroxide in the cathode compartment, and into sulfuric acid in the anode compartment. No zinc whatever was found in either the anode compartment or the cathode compartment. The zinc had been quantitatively retained in the center compartment. The power consumed was very close to 5 kilowatt hours per pound of sodium hydroxide produced.
  • An electrolytic process for the separation of ions of an alkali metal from an aqueous solution containing ions of said alkali metal together with ions of an amphoteric metal from the class consisting of zinc and aluminum which comprises passing a direct electric current through an electrolysis cell which has (a) an anode compartment in which there is an aqueous solution containing hydrogen ions, (b) a cathode compartment in which there is an aqueous solution of the hydroxide of said alkali metal and (c) an intermediate compartment in which there is an aqueous solution containing ions of both said alkali metal and said amphoteric metal, said intermediate compartment being separated from said anode compartment by an anionic permselective diaphragm which contains an anion-exchange resin and being separated from said cathode compartment by a cationic permselective diaphragm whifih Contains a cation-exchange resin.
  • An electrolytic process for the separation of ions of sodium from an aqueous solution containing ions of sodium and ions of zinc which comprises passing a direct electric current through an electrolysis cell which has (a) an anode compartment in which there is an aqueous solution containing hydrogen ions, (b) a cathode compartment in which there is an aqueous solution of sodium hydroxide and (c) an intermediate compartment in which there is an aqueous solution containing ions of sodium and ions of zinc, said intermediate compartment being separated from said anode compartment by an anionic permselective diaphragm which contains an anion-exchange resin and being separated from said cathode compartment by a cationic permselective diaphragm which contains a cation-exchange resin.
  • a process for preparing substantially zinc-free sodium hydroxide and sulfuric acid from a mixture of sodium sulfate and zinc sulfate which comprises passing a direct electric current through an electrolysis cell which has an anode compartment containing aqueous sulfuric acid, a cathode compartment containing aqueous sodium hydroxide and an intermediate compartment containing an aqueous solution of sodium sulfate and zinc sulfate, said intermediate compartment being separated from said anode compartment by an anionic permselective diaphragm which contains an anion-exchange resin and being separated from said cathode compartment by a cationic permselective diaphragm which contains a cationexchange resin.
  • the anionic permselective diaphragm contains a strongly basic quaternary ammonium anion-exchange resin made by first chloromethylating and then aminating with a tertiary amine an insoluble cross-linked copolymer of styrene and divinylbenzene and in which the cationic permselective diaphragm contains a cation-exchange resin which is a sulfonated copolymer of styrene and divinylbenzene.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Water Supply & Treatment (AREA)
  • Health & Medical Sciences (AREA)
  • Urology & Nephrology (AREA)
  • Water Treatment By Electricity Or Magnetism (AREA)
  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
  • Treatment Of Water By Ion Exchange (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)
  • Electrolytic Production Of Metals (AREA)
  • Electrolytic Production Of Non-Metals, Compounds, Apparatuses Therefor (AREA)
US325686A 1952-12-12 1952-12-12 Electrolytic process for the separation of ions of amphoteric and non-amphoteric metals Expired - Lifetime US2723229A (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
BE524792D BE524792A (de) 1952-12-12
DENDAT1071669D DE1071669B (de) 1952-12-12 Herstellung von zink- bzw. ailumimiumfreien Alikailisallzllösuingen
NL82830D NL82830C (de) 1952-12-12
US325686A US2723229A (en) 1952-12-12 1952-12-12 Electrolytic process for the separation of ions of amphoteric and non-amphoteric metals
GB32978/53A GB757928A (en) 1952-12-12 1953-11-27 An electrolytic process for separating alkali metal ions from ions of zinc and/or aluminium
CH327709D CH327709A (fr) 1952-12-12 1953-12-11 Procédé électrolytique pour la séparation d'ions d'un métal alcalin ou d'ammonium d'avec des ions de zinc ou d'aluminium
FR1089388D FR1089388A (fr) 1952-12-12 1953-12-11 Perfectionnements relatifs aux procédés d'électrolyse

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US325686A US2723229A (en) 1952-12-12 1952-12-12 Electrolytic process for the separation of ions of amphoteric and non-amphoteric metals

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US2723229A true US2723229A (en) 1955-11-08

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US (1) US2723229A (de)
BE (1) BE524792A (de)
CH (1) CH327709A (de)
DE (1) DE1071669B (de)
FR (1) FR1089388A (de)
GB (1) GB757928A (de)
NL (1) NL82830C (de)

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2814592A (en) * 1956-11-23 1957-11-26 Sylvania Electric Prod Processes for purifying inorganic materials
US2954336A (en) * 1957-07-30 1960-09-27 Standard Oil Co Universal titrating agent generator
US3004909A (en) * 1955-06-08 1961-10-17 Nalco Chemical Co Electropositive selective permeable membrane and method of production
US3017338A (en) * 1958-03-03 1962-01-16 Diamond Alkali Co Electrolytic process and apparatus
US3038844A (en) * 1961-01-24 1962-06-12 William H Webb Separations by electrodialysis
US3262868A (en) * 1959-09-28 1966-07-26 Ionics Electrochemical conversion of electrolyte solutions
US3305463A (en) * 1962-03-16 1967-02-21 Pittsburgh Plate Glass Co Electrolytic production of dichromates
US3438879A (en) * 1967-07-31 1969-04-15 Hooker Chemical Corp Protection of permselective diaphragm during electrolysis
US3767549A (en) * 1970-09-24 1973-10-23 Asahi Chemical Ind Method for producing basic aluminum chloride
US4051002A (en) * 1975-07-25 1977-09-27 Asahi Glass Company, Ltd. Electrodialysis for aqueous solution of base
US4105532A (en) * 1975-01-09 1978-08-08 Parel Societe Anonyme Improvements in or relating to the electrowinning of metals
DE2743820A1 (de) * 1977-09-29 1979-04-05 Kernforschungsanlage Juelich Verfahren und elektrolytische zelle zum elektrochemischen umsetzen von in einer elektrolytloesung befindlichen stoffen
US4234393A (en) * 1979-04-18 1980-11-18 Amax Inc. Membrane process for separating contaminant anions from aqueous solutions of valuable metal anions
US4728402A (en) * 1985-07-24 1988-03-01 Ogussa Osterreichische Gold- Und Silber-Scheideanstalt Scheid Und Roessler Gesellschaft M.B.H. & Co. K.G. Electrolytic silver refining process
US5141610A (en) * 1988-04-19 1992-08-25 Vaughan Daniel J Electrodialytic process for restoring sodium hydroxide etchants for aluminum
US5198085A (en) * 1990-04-12 1993-03-30 Vaughan Daniel J Restoration of alkali hydroxide etchants of aluminum
WO1998028230A1 (en) * 1996-12-23 1998-07-02 The Scientific Ecology Group, Inc. Electrochemical leaching of soil

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4009410A1 (de) * 1990-03-23 1991-09-26 Basf Ag Verfahren zur elektrochemischen spaltung von alkali sulfaten
CN118320651A (zh) * 2024-05-29 2024-07-12 泰州禾益新材料科技有限公司 一种双单体聚合的聚酰胺纳滤膜的制备方法

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2636852A (en) * 1949-07-09 1953-04-28 Ionics Method of electrodialyzing aqueous solutions and apparatus therefor
US2636851A (en) * 1949-07-09 1953-04-28 Ionics Ion-exchange materials and method of making and using the same

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2636852A (en) * 1949-07-09 1953-04-28 Ionics Method of electrodialyzing aqueous solutions and apparatus therefor
US2636851A (en) * 1949-07-09 1953-04-28 Ionics Ion-exchange materials and method of making and using the same

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3004909A (en) * 1955-06-08 1961-10-17 Nalco Chemical Co Electropositive selective permeable membrane and method of production
US2814592A (en) * 1956-11-23 1957-11-26 Sylvania Electric Prod Processes for purifying inorganic materials
US2954336A (en) * 1957-07-30 1960-09-27 Standard Oil Co Universal titrating agent generator
US3017338A (en) * 1958-03-03 1962-01-16 Diamond Alkali Co Electrolytic process and apparatus
US3262868A (en) * 1959-09-28 1966-07-26 Ionics Electrochemical conversion of electrolyte solutions
US3038844A (en) * 1961-01-24 1962-06-12 William H Webb Separations by electrodialysis
US3305463A (en) * 1962-03-16 1967-02-21 Pittsburgh Plate Glass Co Electrolytic production of dichromates
US3438879A (en) * 1967-07-31 1969-04-15 Hooker Chemical Corp Protection of permselective diaphragm during electrolysis
US3767549A (en) * 1970-09-24 1973-10-23 Asahi Chemical Ind Method for producing basic aluminum chloride
US4105532A (en) * 1975-01-09 1978-08-08 Parel Societe Anonyme Improvements in or relating to the electrowinning of metals
US4051002A (en) * 1975-07-25 1977-09-27 Asahi Glass Company, Ltd. Electrodialysis for aqueous solution of base
DE2743820A1 (de) * 1977-09-29 1979-04-05 Kernforschungsanlage Juelich Verfahren und elektrolytische zelle zum elektrochemischen umsetzen von in einer elektrolytloesung befindlichen stoffen
US4191619A (en) * 1977-09-29 1980-03-04 Kernforschungsanlage Julich Gesellschaft Mit Beschrankter Process for conversion of materials in electrolytic solution
US4234393A (en) * 1979-04-18 1980-11-18 Amax Inc. Membrane process for separating contaminant anions from aqueous solutions of valuable metal anions
US4728402A (en) * 1985-07-24 1988-03-01 Ogussa Osterreichische Gold- Und Silber-Scheideanstalt Scheid Und Roessler Gesellschaft M.B.H. & Co. K.G. Electrolytic silver refining process
US5141610A (en) * 1988-04-19 1992-08-25 Vaughan Daniel J Electrodialytic process for restoring sodium hydroxide etchants for aluminum
US5198085A (en) * 1990-04-12 1993-03-30 Vaughan Daniel J Restoration of alkali hydroxide etchants of aluminum
WO1998028230A1 (en) * 1996-12-23 1998-07-02 The Scientific Ecology Group, Inc. Electrochemical leaching of soil

Also Published As

Publication number Publication date
DE1071669B (de) 1959-12-24
BE524792A (de)
NL82830C (de)
FR1089388A (fr) 1955-03-16
GB757928A (en) 1956-09-26
CH327709A (fr) 1958-02-15

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