Abstract: The present invention provides a novel method of extracting zinc from geothermal brines and synthetic brines which can be performed in a continuous, in-line process.

Abstract: In a process for the treatment of electric arc furnace (EAF) dust, the dust is first subjected to atmospheric leaching with a ferric chloride solution and thereafter subjected to treatment in an autoclave at an elevated temperature and pressure for conversion of low temperature stable goethite (FeO.OH) to a filterable crystalline hematite (Fe.sub.2 O.sub.3) in an acidic chloride solution. Zinc is recovered from the solution by solvent extraction using a solvating extractant followed by stripping and zinc recovery by electrolysis of zinc chloride solution. Lead is separated from the solution by cooling to precipitate lead chloride.

Abstract: Processes are provided for substantially removing base metals and/or cyanide from gold-barren solutions resulting from gold ore processing.

Abstract: Lead and cadmium ions are selectively removed and reclaimed from aqueous liquids containing the ions of these metals using an ion exchange resin which comprises a modified silica gel.

Abstract: Process for the removal of cadmium from solutions of phosphoric acid derived by the sulphuric and nitric digestion of phosphatic rocks, including the following steps:adding to the phosphoric acid solution bromide ions, such as hydrogen bromide or the bromides of alkaline metals, in quantities ranging from 100 to 3500 ppm;adding to the same solution of at least one condensed polyphosphatic compound in a concentration of 1 to 5% by weight;eluting the mixture thus obtained through at least two beds of an ion-exchange resin with a styrene divinylbenzene matrix at a temperature ranging from 15.degree. to 50.degree. C.

Abstract: The present invention provides a novel method of extracting zinc from geothermal brines and synthetic brines which can be performed in a continuous, in-line process.

Abstract: A process for selective separation of germanium-68 from proton irradiated molybdenum targets is provided and includes dissolving the molybdenum target in a hydrogen peroxide solution to form a first ion-containing solution, contacting the first ion-containing solution with a cationic resin whereby ions selected from the group consisting of molybdenum, niobium, technetium, selenium, vanadium, arsenic, germanium, zirconium and rubidium remain in a second ion-containing solution while ions selected from the group consisting of rubidium, zinc, beryllium, cobalt, iron, manganese, chromium, strontium, yttrium and zirconium are selectively adsorbed by the first resin, adjusting the pH of the second ion-containing solution to within a range of from about 0.7 to about 3.

Abstract: A process for selective separation of strontium-82 and strontium-85 from proton irradiated molybdenum targets comprises dissolving the molybdenum target in a hydrogen peroxide solution to form a first solution containing ions selected from a group consisting of molybdenum, niobium, technetium, selenium, vanadium, arsenic, germanium, zirconium, rubidium, zinc, beryllium, cobalt, iron, manganese, chromium, strontium, and yttrium; passing the solution through a first cationic resin whereby ions selected from a group consisting of zinc, beryllium, cobalt, iron, manganese, chromium, strontium, yttrium a portion of zirconium and a portion of rubidium are selectively absorbed by the first resin; contacting the first resin with an acid solution to strip and remove the absorbed ions from the first cationic exchange resin to form a second solution; evaporating the second solution for a time sufficient to remove substantially all of the acid and water from the solution whereby a residue remains; dissolving the residue i

Abstract: Dipicolylamine (DPA) is chemically bound to the surface of a silicate, forming a solid phase particle without substantially decreasing the affinity constant of the DPA for certain ions. Then, the solid phase particle is contacted with the solution, thereby binding an ion to the particle. Subsequently the ion can be stripped from the ligand by treatment with a complexing agent or acid.

Abstract: There is provided a method for treating zinc-containing sulfate solutions which comprises an acid removal for the recovery of a substantially pure sulfuric acid solution and a solution low in acid and containing the zinc and metal impurities from the sulfate solution. The acid removal is carried out by a membrane process that consists of dialysis, electrodialysis or dialysis integrated with electrodialysis. The dialyzate or diluate is subjected to a dual-circuit, side-by-side, simultaneous solvent extraction of zinc and sulfuric acid. In one circuit sulfuric acid is extracted from the dialyzate or diluate and the raffinate from the zinc extraction with an amine-containing extractant. Acid is stripped from the loaded organic with water or an alkaline substance, and is recovered as sulfuric acid or as a sulfate, preferably as ammonium sulfate.

Abstract: A method is disclosed for the quantitative removal and concentration of desired transition metal ions from a source solution which may contain larger concentrations of other metal and H.sup.+ ions. The method comprises bringing the source solution into contact with a compound comprising a pyridine containing ligand covalently bonded through an organic spacer silicon grouping to a solid inorganic support. The pyridine portion(s) of the compound has an affinity for the desired metal ions to form a complex thereby removing the desired metal ions from the source solution. The desired metal ions are removed from the compound by contacting the compound with a much smaller volume of a receiving solution having a greater affinity for the desired metal ions than does the pyridine ligand portion of the compound. The concentrated metal ions thus removed may be recovered by known methods.

Abstract: Metals selected from the group consisting of zinc (II), cadmium (II), nickel (II), cobalt (II), manganese (II), iron (III) and copper (II) from aqueous solutions containing the same are extracted therefrom by contacting said solution with an extractant having the formula ##STR1## wherein R and R.sup.1 are, individually, selected from the group consisting of substituted or unsubstituted alkyl, cyloalkyl, alkoxyalkyl, alkylcycloalkyl, aryl, alkaryl, aralkyl and cycloalkylaryl radicals having 2-24 carbon atoms and X is hydrogen, ammonium or an alkali or alkaline earth metal salt-forming radical.

Abstract: The present invention relates to a method for the selective extraction of the metals gold, silver, platinum or mercury ions or colloidal gold, from an aqueous solution containing at least one of these metal ions which comprises contacting the solution, at a pH of 2 or less, with cells or cell extracts of a microorganism capable of binding these metals for a period of time and under conditions sufficient to allow binding of the metals to the cells or cell extracts.

Abstract: Metal halides are ultrapurified by selective complexation with a complexing gent to form a charged first complex. A ligand forms an oppositely charged second complex with metallic impurities in the metal halide to be purified. A solution containing these complexes is then passed through an ion exchange column and the desired purified metal halide collected. The present method is particularly useful in the production of ultrapure metal halides, such as zirconium fluorinate, for metallic glasses.

Abstract: A method for recovery of metal and cyanide from plating baths and rinse waters includes formation of hydrogen cyanide by acid treatment of such solutions, followed by HCN removal through diffusion across a microporous membrane. The method is applicable in a system wherein soluable metal cyanides and metal cyanide complexes are concentrated through use of a basic anion exchange system. Free hydrogen cyanide is released from the anion exchange system by means of an acid regenerant. In a preferred application of the invention, HCN, once having diffused through the microporous membrane, is neutralized with sodium hydroxide, to form a sodium cyanide solution that can be returned to a plating bath.

Abstract: A process for the extraction of cations from an aqueous effluent. An effective quantity of at least one polymer or copolymer, which is physically or chemically crosslinked, is introduced into the aqueous effluent. The polymer or copolymer is based on one or more units selected from salified acrylic acid, quarternized acrylic acid, and a copolymer comprising from 40 to 60 mole % of acrylic acid and from 60 to 40 mole % of at least one dialkylaminoalkyl acrylate in which each alkyl group contains from 1 to 4 carbon atoms. This process is used to treat aqueous effluents.

Abstract: Improved flue gas purification process features a heavy metal separating process, such as an anion exchange process, in which a scrubbing condensate is treated to remove at least the Hg contained therein prior to extracting the flue ash, which was previously separated and collected, with the scrubbing condensate to extract soluble heavy metals therefrom. A further heavy metal separating process, such as a cation exchange process, in which the scrubbing condensate after the extraction step is treated to remove at least one of Cd and Zn contained therein is also featured and may be performed after the extraction step or after solid/liquid separation of the flue ash and condensate from the extraction step.

Abstract: The compounds of the invention comprise the condensation product, as well as derivatives thereof, of two equivalents of a trimethyl cyclohexane-anhydride acid chloride derivative with one equivalent of an aromatic diamine. The scope of the invention includes the method of using the compounds of the invention as chelating agents for metals, metal ions or ions of metal complexes. In a preferred embodiment of the invention the binding moieties of the cyclohexane derivatives are rigidly held opposite each other, by restricting their rotation about the N-C aryl bonds, in order to more effectively bind the metals or the ions.

Abstract: The purpose of the process is to remove and to recover metals from their aqueous solution by the extraction process. As extractant is used monoesters of phosphonic acid wherein the alkyl group is a phenyl-vinyl group or straight-chained and the ester group is straight-chained. The particular advantage of the process is that the metals can be removed from aqueous solutions to be treated without neutralization of the acid quantity produced during extraction, and this acid solution produced can be circulated e.g. to the stage before the extraction. The process can be used to the removing of metals from the industrial waste waters.

Abstract: Cadmium is removed from an acid, phosphate-containing aqueous medium with the aid of an anion exchanger, in which process, during the removal, iodide or bromide ions are present in a quantity of 100-6000 ppm calculated with respect to the acid phosphate-containing aqueous medium.

Abstract: A process comprises leaching zinc oxide either separately or in conjunction with iron oxides from a partially desulfurized zinc bearing sulfide ore of concentrate. The ore is pretreated to eliminate in a controlled manner sulfur-sulfur-sulfide in the ore yet leaving sufficient residual sulfur-sulfide in the material such that iron values are maintained substantially wholly in the ferrous state, while converting zinc sulfide to zinc oxide without formation of FeO-ZnO complexes. The partially desulfurized material may be selectively leached with a sulfuric acid containing solution under neutral leach conditions to dissolve thereby preferentially the zinc oxide over the iron oxide. Alternatively the material may be leached with a higher concentration of sulfuric acid containing solution to dissolve preferentially zinc oxide and iron oxide simultaneously. The leach liquor may be subsequently treated to electrolytically remove zinc.

Abstract: A method for removing mercury and other related metals such as cadmium, zinc, copper, silver, from a liquid medium. This method comprises the step of contacting the liquid medium with an insoluble composition comprising an suitable insoluble carrier and a cysteine residue covalently fixed at the nitrogen atom thereof to the surface of the carrier.

Abstract: A process is described for the substantially complete recovery of cyanide reagent and metal forming water soluble metal-cyanide complexes contained in mill effluents and waste waters. The process is comprised of a loading cycle wherein the metal-cyanide complexes are adsorbed onto a basic ion exchange resin and the free cyanide containing column effluent is returned to the mill. The metal ions, which are usually mostly copper, nickel and zinc, and the complexing cyanide are eluted in the subsequent regenerant cycle by an acid solution having controlled pH and controlled redox potential, the latter being measured against the saturated calomel electrode. The preferred oxidant to control the redox potential of the regenerant solution is hydrogen peroxide. The generated hydrogen cyanide is sparged with air, or removed by subatmospheric pressure from the regenerant solution, and dissolved in an alkaline scrubber solution for reuse. The metal ions are recovered from a bleed solution.

Abstract: A process for the extraction of metals selected from the group consisting of zinc (II), silver (I), cadmium (II), mercury (II), nickel (II), cobalt (II), and copper (II) from an aqueous solution containing, in addition to said metals, metals selected from the group consisting of calcium (II) and magnesium (II) is disclosed. The process comprises contacting the aqueous solution having an equilibrium pH within the range of about 0.2 to about 3 with an extractant. The extractant comprises an organic-soluble dithiophosphinic acid or ammonium, alkali or alkaline earth metal salt thereof represented by the formula: ##STR1## wherein R.sup.1 and R.sup.2 are the same or different and are selected from the group consisting of substituted or unsubstituted alkyl, cycloalkyl, alkoxyalkyl, alkylcycloalkyl, aryl, alkylaryl, aralkyl and cycloalkylaryl radicals having from about 2 to about 24 carbon atoms and X is either hydrogen or an ammonium, alkali or alkaline earth metal salt forming radical.

Abstract: A method is disclosed for the selective removal of metal ions from plating solutions comprising contacting the plating solutions with liquid organic complexing agents such as oximes or phosphoric acid esters or microporous material, preferably anisotropic, the microporous material being impregnated with such substances. The microporous material may be in various forms, including beads, fibers, sheets and gels. Copper, zinc and iron contaminants are effectively removed from nickel-plating solutions.

Abstract: Metal values are extracted from aqueous solutions containing halide or pseudohalide anion using 1,1'-substituted 2,2'-biimidazole or bibenzimidazole compounds. Useful for the solvent extraction of zinc and copper from chloride leach solutions.

Abstract: Metal values, particularly copper values, are extracted from aqueous solutions containing halide or pseudohalide anion using 6,7 substituted triazolopyrimidine wherein the 6-substituent is a group --CO--OR1 where R1 is a hydrocarbyl group containing from 1 to 35 carbon atoms, preferably an alkyl group and wherein the 7-substituent (R2) is hydrogen or a hydrocarbyl group containing from 1 to 35 atoms wherein R1 and R2 taken together contain a total of from 5 to 35 saturated carbon atoms.

Abstract: A process for selectively stripping and separating iron ions from an organic solvent (A) which comprises bringing the organic solvent (A) containing iron and zinc ions, and containing one or more compounds selected from the group consisting of alkyl phosphoric acid, alkyl-aryl phosphoric acid, alkyl thio phosphoric acid and alkyl-aryl thio phosphoric acid together with a petroleum hydrocarbon as a diluent, into contact with an aqueous solution containing NH.sub.4.sup.+ and F.sup.- ions so as to selectively strip the iron ions into the aqueous solution despite the coexistence of zinc ions.

Abstract: A metal scavenger is composed of an addition product of a polyamine and an epihalohydrin. The addition product contains as substituent or substituents at least one carbodithio group and/or at least one carbodithioate salt group introduced therein by substituting the corresponding number of active hydrogen atom or atoms in the addition product. Metals can be scavenged from waste water by adding the metal scavenger together with at least one of sodium monosulfide, sodium polysulfides and sodium hydrogensulfide.

Abstract: This invention provides processes for selectively recovering silver and gold values from feed materials containing both precious metals, and comprises leaching the feed material with a hot ferric chloride-acid brine leach solution for a time sufficient to dissolve the silver, but wherein the gold is not dissolved and remains with the solid residue. The silver-containing ferric chloride-acid brine leachate is separated from the solid residue containing the gold. The leach solution is then cooled to precipitate the silver as silver chloride. The solid residue containing the gold is then leached with hypochlorous acid to dissolve the gold, and after separating the solids form the gold-containing hypochlorous acid leach solution, the gold is precipitated by contacting the solution with sulfur dioxide. The silver chloride may be further processed in a fused salt electrolysis step at or above the melting point of silver to produce a substantially pure silver and chlorine gas.

Abstract: A method of beneficiation of complex sulfide ores comprises crushing and grinding complex sulfide ore containing sulfides of copper, zinc, iron and other minerals, subjecting the ground ores to differential flotation to obtain a bulk copper-zinc concentrate which is separate from pyrite and gangue, and passing the bulk copper-zinc concentrate through a high-gradient magnetic separator having an open-bore magnetic field filled with a matrix element, so as to recover separately a magnetic copper concentrate and a non-magnetic zinc concentrate. By combining the differential flotation with high-gradient magnetic separation, the present invention enables individual separation of copper and zinc concentrates without using many reagents in high volumes and by a simple process control.

Abstract: A method for preparing a .sup.195m Au-containing liquid is provided. In the method, .sup.195m Hg is adsorbed on an adsorption agent and then the daughter radioisotope .sup.195m Au is eluted from the adsorption agent with an eluant containing a gold-complexing agent. The adsorption agent comprises a mercury ion-binding material having a substantially stronger adsorption affinity for mercury ions than for gold ions.Also disclosed are a radioisotope generator capable of producing a .sup.195m Au-containing liquid and a process for conducting a radiodiagnostic examination on a warm-blooded animal using a .sup.195m Au-containing liquid.

Abstract: A process for the removal of cadmium contained in wet-process phosphoric acid by flotation by means of a cadmium-collector anionic surface active agent and an injected gas in the presence of other impurities including iron and possibly uranium which is characterized in that, in order to improve the removal of cadmium, the iron contained in the phosphoric acid in the trivalent state is reduced to the divalent state before the cadmium collector is introduced into the medium to be purified by flotation.The collector agent is selected from the group of dithiophosphoric acid esters and the alkali metal salts thereof.

Abstract: The process for production of lead from lead sulphide ores involves leaching the ores with a ferric chloride solution, at a temperature from about 70.degree. C. to 105.degree. C., at a pH of from about 4.0 to 0.5, recovering the lead by cementation with metallic zinc, recovering the resultant zinc chloride by solvent extraction, and electrowinning zinc metal from the zinc chloride solution. Chlorine is also electrolytically produced for regenerating ferric chloride for the leaching step.

Abstract: A process for the recovery of anhydrous zinc chloride from aqueous solutions containing zinc chloride and typical impurities, comprising: extracting zinc chloride onto a suitable organic extractant such as TBP; stripping the organic extractant with an organic reagent immiscible in the extractant, such as ethylene glycol; adding ammonia or other ammine donor to the loaded organic strip to precipitate a zinc chloride-ammine composition which may be decomposed to anhydrous zinc chloride by heating. The anhydrous zinc chloride is of high purity suitable for fused salt electrolysis to produce elemental zinc.

Abstract: Zinc is extracted from an aqueous zinc containing brine (3) by contacting the brine with an organic reagent (5) consisting essentially of an extracting agent comprising a quaternary amine salt, a phase modifier, and an organic diluent so as to form a zinc amine complex (7) whereby a substantial portion of the zinc ions in the brine is transferred to the organic phase. The quaternary amine salt is a methyl triakyl ammonium chloride herein the alkyl groups contain from 8 to 10 carbon atoms. The zinc amine complex (7) is then contacted with an aqueous strippant (11) comprising a solution of sodium sulfate in water so as to form a sulfated quaternary amine salt whereby a substantial portion of zinc in the zinc amine complex is stripped therefrom and transferred to the aqueous phase as an aqueous zinc chloride solution (13) from which zinc may be recovered by electrowinning or chemical precipitation.

Abstract: Crystalline transition metal aluminate compounds are formed by reacting transition metal compounds with crystalline hydrous alumina, such as gibbsite, bayerite, norstrandite, boehmite and the like. The crystalline hydrous alumina may be unsupported by a solid substrate or may be supported on a solid substrate or within the pores of a solid substrate, such as a macroporous resin.

Abstract: A process for the treatment of a spent hydrochloric acid solution containing dissolved iron, zinc, and minor amounts of heavy metals to remove such dissolved metals from the solution, which process comprises contacting said solution with metallic iron in a first stage, whereby trivalent iron present in the solution is reduced to divalent iron and certain of said heavy metals may be reduced to elemental form, next, in a second stage, contacting said solution with metallic zinc, whereby any remaining heavy metals are reduced to elemental form, and then extracting zinc, as zinc chloride, from the resulting aqueous phase with an organic liquid containing a complexing agent for zinc chloride.

Abstract: Metal values are extracted from aqueous solutions of metal salts containing halide or pseudo halide ions by pyrimidine, pyrazine or pyridazine derivitives bearing the substituent --(C.dbd.O.X).sub.n where X is the group --OR.sub.1 or --NR.sub.2 R.sub.3 and n is 1, 2 or 3. R.sub.1 is a hydrocarbyl group containing from 1 to 36 carbon atoms and R.sub.2 and R.sub.2 together contain from 1 to 36 carbon atoms. The molecule as a whole contains from 5 to 36 alkyl carbon atoms and may carry further optional substituents. The process is especially useful for the recovery of metals from leach solutions derived from sulphur-containing ores.

Abstract: Metal values are extracted from aqueous solutions of metal salts containing halide or pseudo halide ions by pyrimidine, pyrazine or pyridazine derivatives bearing the substituent --(C.dbd.O.X).sub.n where X is the group --OR.sub.1 or --NR.sub.2 R.sub.3 and n is 1, 2 or 3. R.sub.1 is a hydrocarbyl group containing from 1 to 36 carbon atoms and R.sub.2 and R.sub.2 together contain from 1 to 36 carbon atoms. The molecule as a whole contains from 5 to 36 alkyl carbon atoms and may carry further optional substituents. The process is especially useful for the recovery of metals from leach solutions derived from sulphur-containing ores.

Abstract: New compounds have been prepared from dicyclopentadiene bis(methylamine) which have the following formula ##STR1## wherein substituents A, B, X and Y each are independently selected from radicals including hydrogen, hydroxyalkyl (wherein the alkyl group contains 2-6 carbon atoms) phosphonic, sulfonic, hydroxyethyl- and hydroxypropylsulfonic, methylenephosphonic methylene-, ethylene- and propylenesulfonic, alkylcarboxylic acid radicals (having 2-4 carbon atoms) and the alkali or alkaline earth metal, ammonia and amine salts of any of the phosphonic, sulfonic or carboxylic acid derivatives. At least one of the substituents must be other than a hydrogen. These compounds are useful chelating agents and those containing the methylenephosphonic substituents are good threshold agents.

Abstract: A process is provided for recovering zinc from zinc residues containing iron, and lead. The residue is leached with hydrochloric acid to provide a pregnant liquor containing zinc, iron, and lead. The iron is selectively removed from the pregnant liquor and the zinc extracted from the liquor by an organic solvent extraction system. The zinc is subsequently stripped from the organic solvent using water or hydrochloric acid to provide a zinc chloride solution which is then fed to an electrowinning cell for the production of marketable electrolytic zinc.

Abstract: A process for eluting indium from a chelate resin having a phosphorus atom-containing, chelate-forming group which contains adsorbed indium, which comprises contacting said resin firstly with a primary eluent containing an acid containing no halogen atom in the molecule at a concentration of 0.1N or higher and then with an eluent for indium which is selected from the group consisting of (1) a solution of an acid containing a halogen atom in the molecule, (2) a mixed solution of (a) a metal halide, an ammonium halide or a mixture thereof and (b) an acid and (3) a mixed solution of a sulfide and a base compound.

Abstract: A process for recovery of zinc values from aqueous ammoniacal solutions employing certain alkylsalicylaldoximes or acetophenoximes as the extractant. The method also provides a means for separation of the zinc and copper values present in the aqueous ammoniacal solution. The zinc and copper values are separately recovered from the organic phase by pH controlled stripping.

Abstract: A hydrometallurgical process is provided to electrogalvanize steel, utilizing primary and secondary zinc sources. The process consists of leaching the feed in a mildly acidic solution. The zinc is selectively recovered from the leach liquor in a solvent extraction system and thereafter stripped from the solvent using a stronger acidic solution to provide a strip solution which is fed to an electrogalvanizing bath for electrogalvanizing steel products, e.g., sheet steel, using insoluble anodes. Acidic solutions and organic solvent are recycled in the process.

Abstract: A method is described for precious metal recovery from acidic precious metal-cyanide solutions by means of a weakly-basic anion-exchange material comprising a polymeric felt incorporating radiation-grafted pyridinyl functional groups.

Abstract: A process for the selective recovery of cadmium, molybdenum, zinc, nickel and other metal values from wet process phosphoric acid and other acidic to slightly basic carrier solutions, wherein the metal-bearing solution is contacted with an organophosphene extractant to precipitate the metal values for subsequent separation from the solution. Separation may be effected by mechanical means or by scrubbing with a water-immiscible organic solvent such as kerosene for subsequent recovery of the metal values. The metal specie recovered is determined by the concentration of the organophosphene, which may be selectively adjusted to recover a series of metal values in a sequence of stages.

Abstract: The disclosure relates to a process for liquid/liquid-extraction of heavy metal ions from acid aqueous solutions with the aid of water-insoluble dithiophosphoric acid diesters as extracting agents. More particularly, use is made of phosphoric acid solutions with a P.sub.2 O.sub.5 -content of from 3 to 80 weight %, the solutions being free from emulsion-forming organic contaminants or having previously been freed therefrom in known manner. The resulting aqueous phase is separated from the phase containing the dithiophosphoric acid diester.

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.

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.