Ion Exchanging Or Liquid-liquid Extracting Patents (Class 423/181)
  • Patent number: 4500498
    Abstract: Anhydrous zinc chloride is produced from an aqueous feed solution containing zinc chloride from an aqueous feed solution containing zinc chloride. The zinc chloride is extracted onto an organic extractant known to the art such as tributyl phosphate, primary, secondary or tertiary amines, and quaternary amine salts. The loaded extractant is then stripped with aqueous stripping solution containing ammonium chloride and ammonium hydroxide. The zinc ammine chloride formed in this aqueous stripping solution is separated from the stripping solution and can then be heated to form anhydrous zinc chloride and ammonia. This anhydrous zinc chloride is suitable as a feed material to a fused salt electrolysis process for the production of zinc.
    Type: Grant
    Filed: January 19, 1984
    Date of Patent: February 19, 1985
    Assignee: Cato Research, Inc.
    Inventors: Paul R. Kruesi, William H. Kruesi
  • Patent number: 4500499
    Abstract: An improved process for producing stable, high purity alkali metal or alkaline earth metal ferrate salt products is disclosed. In this process, crude ferrate salts, after being precipitated and separated from a chilled mother liquor, are purified first with a chilled anhydrous, water miscible extraction solvent to remove residual process contaminants therefrom followed by chilled oxidation resistant rinse solvent step, miscible with said extractant, followed by a drying step so as to produce a stable, purified ferrate product which can be safely stored without special provisions. Both batch and continuous modes of operation are disclosed.
    Type: Grant
    Filed: June 1, 1983
    Date of Patent: February 19, 1985
    Assignee: Olin Corporation
    Inventors: Jerry J. Kaczur, John E. Coleman
  • Patent number: 4499057
    Abstract: The invention relates to new industrial products of the general formula ##STR1## a process for the manufacture of these products and their application as extraction agents in hydrometallurgy.
    Type: Grant
    Filed: September 22, 1982
    Date of Patent: February 12, 1985
    Assignee: Societe Nationale des Poudres et Explosifs
    Inventors: Michel Burgard, Marc D. Piteau, Alain J. Rollat, Jean-Pierre G. Senet
  • Patent number: 4477355
    Abstract: A method for removing and recovering ammonium and/or potassium and/or phosphate ions from wastewater is presented which comprises:permitting said wastewater to pass through at least one bed of ion-exchange resins capable of removing selectively those nutrient ionsregenerating those ion-exchange resins with a Na Cl solution or other suitable regenerant solutions so that said nutrient ions may be obtained in a much more concentrated formadding to said regeneration eluates (or, eventually, directly to wastewater) at least one Mg salt, in proper pH conditions so as to precipitate hydrous MgNH.sub.4 PO.sub.4 and/or MgKPO.sub.4, slightly soluble salts of great agronomic value.
    Type: Grant
    Filed: March 30, 1983
    Date of Patent: October 16, 1984
    Inventors: Lorenzo Liberti, Gianfranco Boari, Roberto Passino
  • Patent number: 4477367
    Abstract: Crystalline 2-layer LiOH.2Al(OH).sub.3.nH.sub.2 O, preferably supported by a porous substrate, is prepared by treating crystalline 2-layer LiX.2Al(OH).sub.3.nH.sub.2 O, where X is anion, with a LiOH solution or other hydroxide ion source. The so-formed crystalline 2-layer LiOH.2Al(OH).sub.3.nH.sub.2 O is particularly suitable for exchange of the OH ion with larger X' ions to produce other crystalline 2-layer LiX'.2Al(OH).sub.3.nH.sub.2 O.
    Type: Grant
    Filed: August 30, 1982
    Date of Patent: October 16, 1984
    Assignee: The Dow Chemical Company
    Inventor: John L. Burba, III
  • Patent number: 4464347
    Abstract: In accordance with the invention, spent liquor from an alumina precipitation stage is contacted with an extraction fluid to separate the mixture into a first layer comprising the extraction fluid and at least a portion of the caustic from the spent liquor and a second layer which comprises the remainder of the spent liquor. The spent liquor may then be subjected to a further precipitation to recover further alumina. The spent liquor remaining may be further treated in subsequent extraction steps to concentrate and dispose of undesirable impurities remaining.
    Type: Grant
    Filed: December 27, 1982
    Date of Patent: August 7, 1984
    Assignee: Aluminum Company of America
    Inventor: J. Finley Bush
  • Patent number: 4460474
    Abstract: A process for the extraction of cesium ions from an aqueous solution with an adduct compound in solid form containing a macrocyclical polyether and an inorganic heteropoly acid. The adduct compounds employed comprise an adduct of (a) benzo-15-crown-5 (B-15-C-5); dibenzo-21-crown-7 (DB-21-C-7); or dibenzo-30-crown-10 (DB-30-C-10), with (b) 12-molybdophosphoric acid (HPMo); 12-tungstophosphoric acid (HPW); 12-molybdosilicic acid (HSiMo); 12-tungstosilicic acid (HSiW); or an Na, K, Tl, or NH.sub.4 salt of any of these acids.
    Type: Grant
    Filed: August 27, 1982
    Date of Patent: July 17, 1984
    Assignee: Kernforschungszentrum Karlsruhe GmbH
    Inventors: Ewald Blasius, Karl-Heinz Nilles
  • Patent number: 4452702
    Abstract: A process for the extraction of cesium ions from an aqueous solution with an adduct compound containing a macrocyclical polyether and an inorganic heteropoly acid component. An organic phase in the form of a solution of an adduct compound in a polar organic solvent is prepared. The adduct compound is the product of a crown ether containing at least one species of the structural elements ##STR1## where, in structure I, n represents one of the numbers 0, 1 or 2, the --C--(C).sub.n --O group forms part of the polyether ring and R.sub.1 is H,CH.sub.3, phenyl up to 4 R.sub.1 (.noteq.H); in structure II, the --C--C--O-- group forms part of the polyether ring and R.sub.2 is H,CH.sub.3, t-butyl, pentyl, heptyl, nonyl, (CH.sub.2).sub.9 Ch.sub.3, phenyl up to 2 R.sub.2 (.noteq.H);and in structure III, the --C.dbd.C--O group forms part of the polyether ring and R.sub.3 is H,CH.sub.3, t-butyl, pentyl, heptyl, nonyl, (CH.sub.2).sub.9 CH.sub.9, phenyl up to 2 R.sub.3 (.noteq.
    Type: Grant
    Filed: August 27, 1982
    Date of Patent: June 5, 1984
    Assignee: Kernforschungszentrum Karlsruhe GmbH
    Inventors: Ewald Blasius, Karl-Heinz Nilles
  • Patent number: 4430311
    Abstract: Formation of hydrous alumina in the reticules of a weak-base anion exchange resin, wherein AlCl.sub.3 has been precipitated as hydrous alumina by reaction with ammonia, is improved by employing a subsequent treatment with HCl or with NH.sub.4 Cl and HCl to convert the exchange resin to the chloride form, thereby increasing the reticular volume of the resin, thus permitting subsequent precipitation of additional hydrous alumina therein.
    Type: Grant
    Filed: April 22, 1983
    Date of Patent: February 7, 1984
    Assignee: The Dow Chemical Co.
    Inventors: John M. Lee, William C. Bauman
  • Patent number: 4415677
    Abstract: Macroporous cation exchange resins with sulfonic acid functional groups having polymeric zirconium hydrous oxide contained therein are useful in substantially removing SO.sub.4.sup.= ions from metal salt solutions.
    Type: Grant
    Filed: October 2, 1981
    Date of Patent: November 15, 1983
    Assignee: The Dow Chemical Company
    Inventors: John M. Lee, William C. Bauman
  • Patent number: 4405576
    Abstract: Macroporous cation exchange resins with sulfonic acid functional groups having polymeric hydrous zirconium oxide and polyacrylic acid contained therein are useful in substantially removing sulfate, borate, bicarbonate and/or phosphate ions from alkali metal salt solutions.
    Type: Grant
    Filed: October 2, 1981
    Date of Patent: September 20, 1983
    Assignee: The Dow Chemical Company
    Inventors: John M. Lee, William C. Bauman
  • Patent number: 4395356
    Abstract: A process for removing catalyst residues from poly-1-butene which is disclosed which comprises contacting an organic phase containing the poly-1-butene dissolved in an inert hydrocarbon solvent with an aqueous solution of an alpha-hydroxysulfonic acid and then separating the poly-1-butene-containing phase from the aqueous phase.
    Type: Grant
    Filed: December 22, 1981
    Date of Patent: July 26, 1983
    Assignee: Shell Oil Company
    Inventors: Lynn H. Slaugh, Carl L. Willis
  • Patent number: 4379132
    Abstract: Either commercial yellow phosphorus or a phosphorus sludge is reacted with a slurry of calcium hydroxide in aqueous sodium hydroxide to form a sodium hypophosphite solution containing calcium and hydroxide ions. The solution is neutralized with phosphoric acid or an acid phosphate salt with the co-production of an insoluble calcium phosphate. The neutral solution is contacted with an ion exchange resin charged with sodium ions to remove any remaining calcium ions.
    Type: Grant
    Filed: August 5, 1982
    Date of Patent: April 5, 1983
    Assignee: FMC Corporation
    Inventors: Dennis C. Annarelli, Richard E. Hall
  • Patent number: 4371512
    Abstract: Alkali metal sulfates are produced from an aqueous solution containing alkali metal hydrogen sulfate which comprises contacting the aqueous solution of alkali metal hydrogen sulfate with a hydrophilic solvent, the hydrophilic solvent being effective to extract at least a portion of the sulfuric acid formed as the alkali metal hydrogen sulfate is converted to alkali metal sulfate in the solution, together with at least a portion of the water present; permitting the alkali metal sulfate solid to crystallize; and recovering the solid alkali metal sulfate product. The hydrophilic solvent may then be extracted and separated from the sulfuric acid with a hydrophobic solvent and both solvents can be recovered and recycled.
    Type: Grant
    Filed: February 3, 1981
    Date of Patent: February 1, 1983
    Assignee: Pennzoil Company
    Inventors: John B. Sardisco, Erhart K. Drechsel
  • Patent number: 4348296
    Abstract: Porous substrates containing seeds of hydrous crystalline alumina are contacted with an aqueous solution of alkaline aluminate, thereby causing additional crystalline hydrous alumina to grow on the seeds within the pores of the substrate.
    Type: Grant
    Filed: December 18, 1980
    Date of Patent: September 7, 1982
    Assignee: The Dow Chemical Company
    Inventors: William C. Bauman, John M. Lee, John L. Burba, III
  • Patent number: 4348295
    Abstract: Crystalline hydrous aluminas, Al(OH).sub.3, are reacted with LiX, where X is anion, under appropriate conditions to prepare crystalline compounds conforming substantially to the empirical formulaLiX.2Al(OH).sub.3.nH.sub.2 Owhere X is anion and nH.sub.2 O represents waters of hydration. Depending on the beginning hydrous alumina, some of the crystalline compounds are of a novel 2-layer unit cell structure and some of a 3-layer unit cell structure.
    Type: Grant
    Filed: December 18, 1980
    Date of Patent: September 7, 1982
    Assignee: The Dow Chemical Company
    Inventor: John L. Burba, III
  • Patent number: 4348297
    Abstract: Crystalline LiOH.2Al(OH.sub.3.nH.sub.2 O is reacted in aqueous solution with anions (A) having a valence of 1, 2, or 3 to form novel lithium aluminates conforming substantially to the empirical formula(LiA.sub.x).sub.y.2Al(OH).sub.3.nH.sub.2 Owhere n is the number of waters of hydration, y is the number of lithium atoms present for each 2Al atoms, A has a negative valence of 1, 2, or 3, and x is the reciprocal of the valence of A.
    Type: Grant
    Filed: December 18, 1980
    Date of Patent: September 7, 1982
    Assignee: The Dow Chemical Company
    Inventors: William C. Bauman, John M. Lee
  • Patent number: 4347327
    Abstract: An anion exchange resin, containing Al(OH).sub.3 suspended therein, is reacted with aq. LiOH to form microcrystalline LiOH.2Al(OH).sub.3 which is then reacted with a halogen acid or halide salt to form microcrystalline LiX.2Al(OH).sub.3. The resin, after having a portion of the LiX eluted by using an aqueous wash, is used to recover Li.sup.+ values from aqueous brines.
    Type: Grant
    Filed: November 19, 1979
    Date of Patent: August 31, 1982
    Assignee: The Dow Chemical Company
    Inventors: John M. Lee, William C. Bauman
  • Patent number: 4331785
    Abstract: Compounds represented by the formula ##STR1## and addition polymers thereof where m is an integer from 2 to about 10, X- is chlorine, hydroxy, carboxy or-AC-R).dbd.CH.sub.2-R is hydrogen or methyl, -R' is an ethylene or propylene group and-AC-R).dbd.CH.sub.2is one of ##STR2## These compounds and their addition polymers form complexes with alkali metal or alkaline earth metal salts and permit the concentration of aqueous solutions of said salts. For example, a compound of the formula ##STR3## is polymerized with an azobis(isobutyronitrile) catalyst to form addition polymers of the repeating unit ##STR4## When cross-linked, rendering it water-insoluble, such an addition polymer concentrates an aqueous solution of sodium chloride when contacted with same at about 0.degree. C.
    Type: Grant
    Filed: December 28, 1979
    Date of Patent: May 25, 1982
    Assignee: The Dow Chemical Co.
    Inventors: Thomas A. Chamberlin, Donald A. Tomalia
  • Patent number: 4321235
    Abstract: Alkaline solutions containing sulfate and sodium ions such as uranium leach liquors, are treated with cationic ion exchange resins in the ammonium form to form a solution containing soluble ammonium salts and complexes; the solution is further treated to convert the soluble sulfates into insoluble sulfates and, in the case of uranium, further treating to separate the uranium by heat and/or acidification. The ammonium can be recovered and reused as ammonium carbonate to regenerate the ion exchange resin whereby sodium ions are eluted from the resin in the form of sodium carbonate which is converted to sodium hydroxide and re-cycled for use as leaching solution.
    Type: Grant
    Filed: February 8, 1978
    Date of Patent: March 23, 1982
    Assignee: Compagnie Generale des Matieres Nucleaires (COGEMA)
    Inventors: Pierre Mouret, Georges Lyaudet, Angelo Sialino, Rino Berri
  • Patent number: 4291001
    Abstract: Improvements are made in the process wherein Li.sup.+ values are recovered from dilute aqueous solution by the use of an anion exchange resin composite containing crystalline LiX.2Al(OH).sub.3, where X is halide. The improvements derive from enriching the Li.sup.+ containing solution with a non-competing metal salt (e.g., NaCl) prior to the Li.sup.+ removal, thereby achieving higher Li.sup.+ loading of the resin composite and obtaining more concentrated eluates.
    Type: Grant
    Filed: December 26, 1979
    Date of Patent: September 22, 1981
    Assignee: The Dow Chemical Company
    Inventors: Wendy J. Repsher, Kirby T. Rapstein
  • Patent number: 4261961
    Abstract: A process for liquid-liquid ion exchange of alkali metal ions. An alkaline aqueous phase containing potassium ions together with other alkali metal ions is contacted with an organic phase containing a polyol-boron-alkali metal complex. The organic phase preferentially extracts potassium values from the aqueous phase. The potassium values are separated from the polyol-boron-alkali metal complex by, for example, stripping with dilute sulfuric acid.
    Type: Grant
    Filed: November 30, 1979
    Date of Patent: April 14, 1981
    Assignee: Kerr-McGee Chemical Corporation
    Inventor: Robert E. Davis
  • Patent number: 4235717
    Abstract: Ion retardation resins particularly useful for desalting caustic solutions are prepared by employing ion exchange resins consisting essentially of a mixture of a reticular, insoluble, cross-linked styrene/divinylbenzene copolymer with an entrapped non-leachable polymer of acrylic acid contained therein and where the amount of carboxylic acid groups on the polyacrylic acid are in substantial excess over the amount needed to react with all the quaternary ammonium groups which are nuclear substituted on the styrene copolymer chains.
    Type: Grant
    Filed: September 22, 1978
    Date of Patent: November 25, 1980
    Assignee: The Dow Chemical Company
    Inventors: John M. Lee, William C. Bauman
  • Patent number: 4230678
    Abstract: An improvement in processes for recovering aluminum from alunite ore which processes include roasting the ore to remove water of hydration, removing sulfur and potassium compounds from the roasted ore by a procedure including a first leaching step resulting in a residue and a solution containing potassium sulfate, effecting partial recovery of potassium sulfate from the solution by crystallization with some potassium sulfate being bled off from the mother liquor, converting aluminum values in the residue to alkali metal aluminates by digesting the residue with alkali metal hydroxide including a substantial amount of sodium hydroxide, removing silicon from the alkali metal aluminates leaving a waste desilication product, recovering aluminum values from the desilicated aluminates by precipitation, circulating the mother liquor from the precipitation step to digestion as contaminated sodium hydroxide is bled off, the improvement which comprises enhancing the economics of the overall process by introducing therei
    Type: Grant
    Filed: February 14, 1979
    Date of Patent: October 28, 1980
    Assignees: Earth Sciences, Inc., National Steel Corporation, Southwire Company
    Inventors: George J. Hartman, Vernon R. Ewing
  • Patent number: 4221767
    Abstract: An anion exchange resin, containing Al(OH).sub.3 suspended therein, is reacted with aq. LiOH to form microcrystalline LiOH.2Al(OH).sub.3 which is then reacted with a halogen acid or halide salt to form microcrystalline LiX.2Al(OH).sub.3. The resin, after having a portion of the LiX eluted by using an aqueous wash, is used to recover Li.sup.+ values from aqueous brines.
    Type: Grant
    Filed: September 5, 1978
    Date of Patent: September 9, 1980
    Assignee: The Dow Chemical Company
    Inventors: John M. Lee, William C. Bauman
  • Patent number: 4193772
    Abstract: In a coal gasification operation or similar conversion process carried out in the presence of an alkali metal-containing catalyst wherein solid particles containing alkali metal residues are produced, alkali metal constituents are recovered for the particles by contacting or washing them with an aqueous solution containing calcium or magnesium ions in an alkali metal recovery zone at a low temperature, preferably below about 249.degree. F. During the washing or leaching process, the calcium or magnesium ions displace alkali metal ions held by ion exchange sites in the particles thereby liberating the ions and producing an aqueous effluent containing alkali metal constituents. The aqueous effluent from the alkali metal recovery zone is then recycled to the conversion process where the alkali metal constituents serve as at least a portion of the alkali metal constituents which comprise the alkali metal-containing catalyst.
    Type: Grant
    Filed: June 5, 1978
    Date of Patent: March 18, 1980
    Assignee: Exxon Research & Engineering Co.
    Inventor: David W. Sharp
  • Patent number: 4169130
    Abstract: Gallium values are recovered from highly basic aqueous solutions thereof, especially from sodium/aluminum liquors of Bayer process origin, by liquid/liquid extraction with a water immiscible organic phase comprising an organic solvent and a dissolved, water-insoluble substituted hydroxyquinoline, said recovery being characterized in that at least the step of extracting the gallium values is conducted under an inert atmosphere.
    Type: Grant
    Filed: July 11, 1978
    Date of Patent: September 25, 1979
    Assignee: Rhone-Poulenc Industries
    Inventors: Jacques Helgorsky, Alain Leveque
  • Patent number: 4159311
    Abstract: Lithium is preferentially extracted from brine containing Li salts along with salts of other metals, e.g. Na, Ca, Mg, K, and/or B, by contacting the brine with a particulate anion exchange resin having suspended therein a microcrystalline form of LiX.sup.. 2A1 (OH).sub.3, where X=halide.
    Type: Grant
    Filed: September 5, 1978
    Date of Patent: June 26, 1979
    Assignee: The Dow Chemical Company
    Inventors: John M. Lee, William C. Bauman
  • Patent number: 4154801
    Abstract: Highly purified alkali metal hydroxide and carbonate solutions are obtained by treating self-contaminated solutions thereof with composite ion exchange resin bodies having low residual amounts of quaternary ammonium cation not intimately associated with carboxylate anions to minimize inorganic chloride and chlorate anion leakage.
    Type: Grant
    Filed: February 1, 1978
    Date of Patent: May 15, 1979
    Assignee: The Dow Chemical Company
    Inventor: Robert M. Wheaton
  • Patent number: 4116858
    Abstract: Lithium is preferentially extracted from brine containing Li salts along with salts of other metals, e.g. Na, Ca, Mg, K, and/or B, by contacting the brine with a particulate anion exchange resin having suspended therein a microcrystalline form of LiX.2Al(OH).sub.3, where X = halide.
    Type: Grant
    Filed: July 5, 1977
    Date of Patent: September 26, 1978
    Assignee: The Dow Chemical Company
    Inventors: John M. Lee, William C. Bauman
  • Patent number: 4116857
    Abstract: Magnesium values are selectively recovered from salt brines, even salt brines which contain competing ions such as Li.sup.+, Ca.sup.++, and Sr.sup.++, by contacting the brine with an anion exchange resin which has dispersed therein a microcrystalline structure of the formula MgX.sub.2.2Al(OH).sub.3, where X is a halide.
    Type: Grant
    Filed: July 5, 1977
    Date of Patent: September 26, 1978
    Assignee: The Dow Chemical Company
    Inventors: John M. Lee, William C. Bauman
  • Patent number: 4116856
    Abstract: An anion exchange resin, containing Al(OH).sub.3 suspended therein, is reacted with aq. LiOH to form microcrystalline LiOH.2Al(OH).sub.3 which is then reacted with a halogen acid or halide salt to form microcrystalline LiX.2Al(OH).sub.3. The resin, after having a portion of the LiX eluted by using an aqueous wash, is used to recover Li.sup.+ values from aqueous brines.
    Type: Grant
    Filed: July 5, 1977
    Date of Patent: September 26, 1978
    Assignee: The Dow Chemical Company
    Inventors: John M. Lee, William C. Bauman
  • Patent number: 4008307
    Abstract: A process for the production of monobasic potassium phosphate from wet process phosphoric acid and potassium sulfate by ion exchange. The application of the process is the production of monobasic potassium phosphate by ion exchange from wet phosphoric acid produced by the reaction of sulfuric acid on apatite rock and by-product potassium sulfate from processes for the recovery of aluminum from alunite.
    Type: Grant
    Filed: June 2, 1975
    Date of Patent: February 15, 1977
    Assignees: Southwire Company, National Steel Corporation, Earth Sciences, Inc.
    Inventors: Kent W. Loest, Vernon R. Ewing
  • Patent number: 3996334
    Abstract: An improvement in processes for recovering aluminum from alunite ore which processes include roasting the ore to remove water of hydration, removing sulfur and potassium compounds from the roasted ore by a procedure including a final leaching step resulting in a residue and a solution containing potassium sulfate, effecting partial recovery of potassium sulfate from the solution by crystallization with some potassium sulfate being bled off from the mother liquor, converting aluminum values in the residue to alkali metal aluminates by digesting the residue with alkali metal hydroxide including a substantial amount of sodium hydroxide, removing silicon from the alkali metal aluminates leaving a waste desilication product, recovering aluminum values from the desilicated aluminates by precipitation, circulating the mother liquor from the precipitation step to digestion as contaminated sodium hydroxide is bled off, the improvement which comprises enhancing the economics of the overall process by introducing therei
    Type: Grant
    Filed: June 2, 1975
    Date of Patent: December 7, 1976
    Assignees: Southwire Company, National Steel Corporation, Earth Sciences, Inc.
    Inventors: George J. Hartman, Vernon R. Ewing
  • Patent number: 3971843
    Abstract: The recovery of gallium present in aqueous solution which may also contain a compound of aluminum and sodium, in which the aqueous solution is contacted with a substituted hydroxyquinoline in solution in an organic solvent immiscible with water and under highly alkaline conditions whereby gallium and sodium and aluminum, when present, go into the organic phase, and in which the gallium can be separated from the sodium and aluminum by contacting the organic phase with a concentrated dilute solution of an inorganic acid to remove sodium and aluminum from the organic phase and then contacting the remaining organic phase with a more concentrated solution of inorganic acid to remove the gallium.
    Type: Grant
    Filed: July 3, 1975
    Date of Patent: July 27, 1976
    Assignee: Rhone-Poulenc Industries
    Inventors: Jacques Helgorsky, Alain Leveque
  • Patent number: 3961034
    Abstract: Filtrate from a formate-sodium hydrosulfite preparation contains valuable amounts of sodium formate and sodium bisulfite, which are raw materials for the synthesis of sodium hydrosulfite. The filtrate also contains sodium thiosulfate which is a known catalyst for the decomposition of sodium hydrosulfite and, therefore, must not be introduced in with the raw materials. Accordingly the method concerns removing the sodium thiosulfate by means of ion exchange with a resin and directing the valuable sodium bisulfite and sodium formate effluent including methanol and water to a distillation column.
    Type: Grant
    Filed: September 25, 1974
    Date of Patent: June 1, 1976
    Assignee: Virginia Chemicals Inc.
    Inventors: Logan C. Bostian, Charles E. Winslow
  • Patent number: 3953568
    Abstract: A method of simultaneously obtaining separate enriched fractions of heavier and lighter isotopes from mixtures thereof with the use of an ion exchange resin column by passing a ligand body containing this isotope mixture through the column. The isotopes, as they are passed through the column, are present in the forms of ligand-containing coordination compounds having different valence states and are followed by an eluant and form a band which travels through the column, the front and rear portions of which are respectively enriched in one of the isotopes and depleted in the other.
    Type: Grant
    Filed: July 17, 1972
    Date of Patent: April 27, 1976
    Inventors: Maomi Seko, Hidetake Kakihana
  • Patent number: 3948791
    Abstract: An ion exchanger consisting of crushed lignite or brown coal retaining alkali ions, which is obtained by immersing the particles in a dilute caustic alkali solution. The concentration of the caustic alkali ranges from 2 to 20 weight percent, preferably from 3 to 10 weight percent. Following the treatment with the alkali, the system is washed with an acid with a pH of 3 to 7 to remove the alkali liquid. The resultant lignite has less than 4 meq/g, for instance 2.60 to 3.50 meq/g, of sodium ions and exhibits abilities of ion exchange. By treating the alkali treated lignite with hydrochloric acid or sulfuric acid it is possible to retain hydrogen ions, and by using a solution of a calcium salt such as calcium chloride calcium ions can be retained. Thus, calcium ions or potassium ions may be exchanged with cations of a salt of metal of Group second in the periodic table such as calcium, magnesium, barium and zinc.
    Type: Grant
    Filed: August 20, 1973
    Date of Patent: April 6, 1976
    Assignee: Japan Metals and Chemicals Co., Ltd.
    Inventors: Mitsuharu Tominaga, Mamoru Mimori, Kinnosuke Okuda