Abstract: The metal value separation efficiencies of alkyl aromatic sulfonic acid in solvent-extraction processes are enhanced by the addition to the solvent-extractant of a fused ring aromatic N-alkyl triazole and, optionally, an aliphatic .alpha.-hydroxy oxime. Especially important applications for the improved solvent-extractant are in the separation and recovery of copper from iron, cobalt from nickel, copper from cobalt, cobalt from zinc, nickel from zinc, zinc from iron, nickel from iron, copper from nickel, copper from iron and copper fron zinc.

Abstract: A process for treating an acid waste liquid containing Fe ions which has been used for acid washing of metallic materials or articles, comprising the first stage where an organic solvent (A) is added to the acid waste liquid to extract Fe ions, the second stage where an acid is added to the resulting acid waste liquid to convert chemical species of remaining metal salts and increase the hydrogen ion concentration followed by addition of an organic solvent (B) to recover the mineral acid of concern by extraction, the third stage where an organic solvent (C) is added to the resulting acid waste liquid to extract and recover other required mineral acids, and regenerating each of the organic solvents (A), (B) and (C) in respective stages.

Abstract: Cobalt catalyst values are recovered from mother liquors remaining from oxidations to mono- or polycarboxylic acids in lower aliphatic monocarboxylic acids in presence of catalysts comprising cobalt and bromide ions by (1) if necessary, adjusting the cobalt and bromide concentrations so that they are within specified limits (2) adsorbing cobalt and bromide ions (differentially with respect to extraneous ions) on a strongly basic anion exchange resin and (3) desorbing cobalt and bromide ions with lower aliphatic monocarboxylic acid containing more than 10% by weight of water.

Abstract: A method for treating nonferrous metal hydroxide sludge waste to separate and recover the nonferrous metals therein wherein the waste is first mixed with an alkali hydroxide or carbonate, dried, and then roasted and the water-insoluble residue in the roasted material is treated with sulfuric acid to produce an acid-insoluble residue and a sulfuric acid solution containing copper, aluminum and chromium and thereafter, separating the copper from this solution by liquid-liquid extraction and thereafter, separating the aluminium, chromium, zinc and nickel from the remaining solution by separate liquid-liquid extraction steps.

Abstract: A method for extracting nickel from aqueous solutions thereof which contain large amounts of alkali metal ions by contacting the aqueous solution with an extraction agent comprising an organic solution of di-2-ethylhexyl phosphoric acid and naphthenic acid.

Abstract: A process for treating very dilute solutions containing ecologically noxious heavy metal ions, in which the solutions are made acceptable for return to the environment, and the typically valuable heavy metal present in the solution is recovered at an economic profit. The dilute solution is flowed through an ion exchange resin, as a cross-linked polystyrene having quaternary ammonium functional groups which hold the heavy metal ions, allowing an ecologically benign effluent to return to the environment or the water to be re-used in industrial processing. Typically, an alkali metal halide is subsequently placed in contact with the resin to recover the heavy metal ion for subsequent reduction to a solid.

Abstract: Process for treating aqueous acidic solutions of cobalt and nickel values using certain fluorinated .beta.-diketones wherein the cobalt values are preferentially stripped from the loaded organic phase. Variations include preferential extraction of cobalt values, recovery of nickel from the raffinate and a second stripping step to recover nickel from the loaded organic.

Abstract: A method for recovering nonferrous metal values from hydroxide sludge wastes containing same by first chlorinating the aqueous waste to oxidize the chromium therein, separating the insoluble components therefrom and treating the resulting Cr(VI) solution in a fixed bed anion exchanger to separate the Cr(VI) from the solution, separating the copper from the aqueous solution by liquid-liquid extraction, separating the zinc from the copper-free solution by liquid-liquid extraction, precipitating and separating the aluminum in the form of hydroxide from the zinc-free solution and then separating the nickel from the aluminum-free solution by liquid-liquid extraction, and recovering the nonferrous metals from the respective solutions and precipitates by conventional procedures.

Abstract: A novel class of extractants and a method of using the extractants in the hydrometallurgical recovery of nickel and cobalt metal. The extractants comprise a water immiscible organic solvent system containing solubilized mercaptide anions. In an important embodiment of the invention, the mercaptide anions are generated by solubilizing an alkali metal mercaptide in a polar organic solvent capable of solvating alkali metal ions. Alternatively, an organic solution of a mercaptan is exposed to an aqueous solution of NaOH or KOH to produce the mercaptide anion.The extractants are used by being contacted with cobalt, nickel, or cobalt and nickel pregnant aqueous solutions. On mixing, the cobalt and/or nickel values are taken up by the organic as cobalt or nickel mercaptides. These may then be stripped of cobalt and nickel by treatment with an aqueous alkaline solution and carbon monoxide.

Abstract: A process for separating nickel and cobalt present in a sulfate solution includes using a cationic extractant to extract both metals, treating the loaded cationic extractant with an aqueous chloride or thiocyanate solution to back-extract the cobalt and thereafter recovering the cobalt from the back-extraction aqueous solution by solvent extraction or ion exchange with an anionic extractant.

Abstract: A novel class of extractants and a method of using the extractants in the hydrometallurgical recovery of nickel and cobalt metal. The extractants comprise a water immiscible organic solvent system containing solubilized mercaptide anion. In an important embodiment of the invention, the mercaptide anions are generated by adding compounds containing both a thiol group and an amine group such as aminoethanethiols or amides of thioglycolic acids to water immiscible organic solvents, preferably of polar character. These systems generate the required mercaptide anions by undergoing an internal acid dissociation.The extractants are used by being contacted with cobalt, nickel, or cobalt and nickel pregnant aqueous solutions. On mixing, the cobalt and/or nickel values are taken up by the organic as cobalt and nickel mercaptides. These may then be stripped of cobalt and nickel by treatment with an aqueous alkaline solution and carbon monoxide.

Abstract: A novel class of extractants and a method of using the extractants in the hydrometallurgical recovery of nickel and cobalt metal. The extractants comprise a water immiscible organic solvent system containing solubilized mercaptide anions. In an important embodiment of the invention, the mercaptide ions are generated by adding a mercaptan to a mixed water immiscible solvent comprising a basic compound such as an amine, preferably a tertiary amine, and a polar component such as an alcohol, whereby the mercaptan undergoes acid dissociation.The extractants are used by being contacted with cobalt, nickel, or cobalt and nickel containing aqueous solutions. On mixing, the cobalt and/or nickel values are taken up by the organic as cobalt or nickel mercaptides. These may then be stripped of cobalt and nickel by treatment with an aqueous alkaline solution and carbon monoxide.

Abstract: From roasted products of used catalysts from hydrotreatment desulfurization of petroleum, valuable molybdenum, vanadium, cobalt and nickel are recovered easily and a high percent recovery by means of a combination of simple chemical procedures and also inexpensive chemicals. The recovered metal components can be reused for preparing new catalysts and the like.

Abstract: A process for extracting metal values from aqueous solutions of metal salts which comprises the steps of contacting the aqueous solution with a solution in a water-immiscible organic solvent of one or more o-hydroxyaryloximes containing at least 3 aliphatic or alicyclic carbon atoms and which are strong metal extractants and one or more alkylphenols optionally containing one chlorine atom or one cyano group, separating from the aqueous phase the solvent phase containing metal in the form of a complex with the o-hydroxyaryloxime contacting the solvent phase with an aqueous mineral acid, and separating the solvent phase from the aqueous phase containing metal in the form of a salt with the mineral acid.

Abstract: Extraction means for the selective extraction of nickel from aqueous solutions thereof, being an open-pore polyurethane foam supporting in its matrix a dioxime of the general formula ##STR1## wherein R and R' each designate an alkyl, aryl, aralkyl, alkaryl or a heterocyclic group, which may be substituted by a non-interfering substituent, or R and R' may form together a ring-structure so as to form cyclohexanedione glyoxime; optionally together with a plasticizer.

Abstract: Heavy metal ions are recovered from a dilute aqueous solution by flowing the solution through either a single bed of ion-absorbing material in successive forward and reverse directions, or through a first bed of ion-absorbing material and thereafter through a second bed of ion-absorbing material in the reverse direction of flow. The reversal of flow is to periodically mechanically agitate a bed of ion-absorbing material to dislodge contaminants, such as gelatin.The method is accomplished by using one enclosed vessel, or a pair of enclosed vessels, that have valves to control the direction of flow. A timing device preferably automatically reverses the direction of flow about each hour.After a relatively large number of reversals of flow the heavy metal ions are recovered from the ion-absorbing material and the same is regenerated in the process to again absorb ions from the dilute aqueous solution.

Abstract: This invention provides a two-stage leaching procedure for manganese nodules for obtaining directly in one leaching stage the metal values other than manganese in one ammoniacal aqueous solution. The manganese nodules are reduced and then leached initially utilizing a solution of an ammonium salt, e.g., ammonium sulfate, to selectively leach out the manganese value, followed by a second stage leaching with an ammoniacal solution, to leach out the nickel, cobalt and copper values. The nickel, cobalt and copper values can then be individually separated from the second leach solution by liquid ion exchange extraction.

Abstract: A process for removing zinc from an aqueous solution of a nickel salt by liquid-liquid extraction using as the extraction agent an organic phosphoric acid dissolved in an organic solvent, adding a strongly oxidizing substance at an elevated temperature to the aqueous phase emerging from the extraction to precipitate the cobalt as a hydroxide and decompose the organic phase left in the aqueous phase and to adsorb it into the cobalt hydroxide precipitate, and finally separating it from the pure aqueous nickel salt solution.

Abstract: An extraction agent composition comprising in addition to one or more conventional extraction agents at least one agent, preferably a strong organic acid, affecting the phase interface tension for diminishing the drop size of the dispersed phase and for accelerating the conversion of the material from one phase to another for the separation of nickel (II) and cobalt (II) from each other from aqueous solutions containing both nickel and cobalt. By using said composition the separation can occur regardless of the type of counter-ion, i.e. said separation can take place from sulphate, nitrate and chloride solutions. Basing the separation on a high chloride content or on the necessity of oxidizing the cobalt being present into a trivalent state has been avoided by the addition of a small amount of strong organic acid.

Abstract: There is provided a process for chelating non-alkali metal ions comprising contacting said metal ions with a phosphorus chelating compound having a formula selected from the group consisting of: ##STR1## WHERE R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7 and R.sub.8 are selected from the group consisting of hydrogen, alkali metal and ammonium, X is selected from the group consisting of hydrogen, alkyl, alkenyl, aryl, chloroalkyl, chloroaryl, and halogen of atomic weight 35 to 80, Y is selected from the group consisting of hydroxyl, phenyl and halogen of atomic weight 35 to 80 and Z is selected from the group consisting of hydrogen, phenyl and halogen of atomic weight 35 to 80.

Abstract: A method is disclosed for removing arsenic by solvent extraction from a copper and/or nickel bearing aqueous solution containing about 100 to 600 gpl sulphuric acid. The method comprises contacting the solution with an organic solution consisting of about 5 to 80% by volume of tributylphosphate in an organic diluent, and subsequently stripping the arsenic from the loaded organic solution with a suitable stripping agent. Particularly, when the sulphuric acid concentration in the aqueous solution is lower than 300 gpl, the organic solution advantageously comprises up to about 15% of a quaternary ammonium reagent. Preferred quaternary ammonium reagents are tricaprylmethyl ammonium chloride and mixtures of tri-C.sub.8 -C.sub.10 methylammonium chlorides.

Abstract: This invention relates to a process for recovery of waste H.sub.2 SO.sub.4 and HCl which are used for pickling metallic materials and articles and contain a large quantities of Fe ions. Furthermore, it offers a process for the recovery of H.sub.2 SO.sub.4 and HCl from waste H.sub.2 SO.sub.4 which contains large amounts of Fe ions after removal of Ti ions by a hydrolysis process in the production of TiO.sub.2 and also for the recovery of high-purity electrolytic iron or iron hydroxide.

Abstract: A process for the extraction of alumina from aluminum-containing silicates is disclosed. The process comprises acid leaching of the raw material, iron extraction, precipitation of the aluminum fraction as the aluminum chloride hexahydrate, removal of sodium chloride and calcination to alumina. The process can be made continuous with substantial regeneration and recycling of process components.

Abstract: A process for recovering metallic cobalt from an aqueous ammoniacal solution containing dissolved cobalt and other metals as ammine sulphates with substantially all the dissolved cobalt being in cobaltic form. The process includes contacting the solution with a water immiscible liquid ion exchange reagent dissolved in an inert organic diluent to selectively substantially completely extract the other metals from the solution and produce an organic extractant loaded with the other metals and an aqueous cobalt bearing raffinate substantially free of the other metals. The cobalt bearing raffinate is separated from the loaded organic extractant and the loaded organic extractant is washed to remove substantially all ammonia therefrom. The other metals are stripped from the washed organic extractant which is then recycled to treat further solution. Cobalt is recovered from the raffinate.

Abstract: Novel 2-hydroxyiminoacetic acids of the formula ##STR1## where R is an aromatic hydrocarbyl group substituted with one or more aliphatic chains of at least four carbon atoms are excellent for the extraction of metal values from acidic metal - containing aqueous solutions, particularly for the separation of Cu from Fe, Ni from Co and Ca from Mg.

Abstract: Alumina is recovered from aluminum sulfate leach liquors by treatment of the liquor with HCl gas to the point of incipient crystallization of AlCl.sub.3.6H.sub.2 O, extraction of the resulting solution with a tertiary amine to remove iron, further treatment with HHl gas to precipitate AlCl.sub.3.6H.sub.2 O and roasting of the AlCl.sub.3.6H.sub.2 O to Al.sub.2 O.sub.3.

Abstract: Process for the recovery of uranium from wet process phosphoric acid solution in which an organic extractant, containing uranium values and dissolved iron impurities and comprising a dialkylphosphoric acid and a trialkylphosphine oxide dissolved in a water immiscible organic solvent, is contacted with a substantially iron-free dilute aqueous phosphoric acid to remove said iron impurities. The removed impurities are bled from the system by feeding the resulting iron-loaded phosphoric acid to a secondary countercurrent uranium extraction operation from which they leave as part of the uranium-depleted acid raffinate. Also, process for recovering uranium in which the extractant, after it has been stripped of uranium values by aqueous ammonium carbonate, is contacted with a dilute aqueous acid selected from the group consisting of H.sub.2 SO.sub.4, HCl, HNO.sub.3 and iron-free H.sub.3 PO.sub.4 to improve the extraction efficiency of the organic extractant.

Abstract: A mixture of metal hydroxides is leached with an ammoniacal carbonate solution, to dissolve nickel, copper and zinc. Metal is recovered from the leaching solution. The solid leaching residue is leached with sulphuric acid at a pH of 1.5- 3, to dissolve a further amount of nickel, copper and zinc. The acidic leaching solution is passed to the ammoniacal leaching process.

Abstract: An organic liquid extractant of at least one oxime, selected from the group consisting of ketoximes and .alpha.-hydroxyoximes dissolved in an organic solvent, useful in separating nickel from cobalt in process solutions or in recovering both nickel and cobalt from process solutions, is treated with a salt of hydroxylamine at intervals to maintain the activity of the oxime in the extractant. The organic extractant can also contain sulfonic acids to facilitate treatment of more acid process solutions and is treated with a hydroxylamine salt to regenerate oxime degraded by the highly acid process solutions, the extractant itself and the concentrated acidic stripping solutions.

Abstract: Soot produced in the combustion of fuel oil contains valuable metals, such as vanadium and nickel. The soot can be disposed of, and the valuable metals can be recovered, by leaching the soot with an aqueous solution of sulphuric acid, to extract part of the metal content from the soot, combusting the soot thus leached, and leaching the combustion residue with an aqueous solution of sulphuric acid, to extract an additional part of the metal content. The solution produced in this second leaching process is preferably returned to the leaching of the soot. Metals can be recovered in a way known per se from the solution produced in the leaching of the soot.

Abstract: New chelate exchange resins capable of selective recovery of copper, nickel, and other valuable metals from an acidic aqueous leach liquor are prepared by reacting a crosslinked haloalkyl polymer matrix resin (I) with certain aminopyridines (II) to give a resin (III) ##STR1## with pendent methyleneaminopyridine groups attached to the matrix resin. Particularly useful resins are obtained by reacting chloromethylated styrene-divinylbenzene copolymer beads with an aminomethylpyridine, such as 2-picolylamine, N-methyl-2-picolylamine, N-(2-hydroxyethyl)-2-picolylamine, N-(2-methylaminoethyl)-2-picolylamine, or bis-(2-picolyl)amine. At a typical copper ore leach liquor pH of about 2, the picolylamine resins will absorb 15-30 mg copper/ml resin with a 5-10 fold selectivity for copper over ferric iron.

Abstract: A novel process for extracting, concentrating, and isolating nickel and cobalt from aqueous solution thereof. A cobalt and/or nickel bearing solution is contacted with an extractant comprising a substantially water immiscible organic solvent containing solubilized mercaptide anion to form water insoluble cobalt and nickel mercaptides in the organic phase. The organic phase is then separated from the raffinate and contacted with an alkaline solution and carbon monoxide to produce nickel and cobalt carbonyl compounds. Typically, the nickel carbonyl produced is gaseous Ni(CO).sub.4 which may be easily isolated by known methods from other components in the off-gas stream. Pure nickel metal is then obtained from the nickel tetracarbonyl by known methods. The cobalt carbonyl compound produced is typically water soluble carbonyl cobaltate ion, Co(CO).sub.4.sup.-, which may be oxidized to form water insoluble cobalt carbonyl compounds.

Abstract: This invention provides a leaching procedure for manganese nodules for obtaining directly from a leaching stage all of the metal values, including manganese, utilizing an ammoniacal aqueous solution. The manganese nodules are reduced and then leached utilizing an ammoniated solution of an ammonium salt comprising at least about 150 grams per liter of ammonium ion and at least 0.83 Normal in the anion, other than hydroxyl. The resultant leach solution comprises the dissolved manganese, nickel, cobalt and copper values from the nodule ore, and can subsequently be treated, as by liquid ion exchange, to separate out the individual metal values.

Abstract: A process for separating cobalt from nickel in an aqueous acid solution containing the above metals, which comprises contacting said solution with an organic phase comprising (a) 65-98% by volume of a concentrated alpha-hydroxyoxime extractant, a 1% by volume solution of which in xylene has per liter a maximum loading capacity of about 0.864 g. of copper, and (b) 2-35% by volume of an organophosphoric acid of the general formula: ##STR1## wherein R.sub.1 represents an alkyl, aryl or aralkyl radical, while maintaining the pH of said solution between 1 and 6, whereby cobalt is extracted from the aqueous phase to the organic phase and separating the resultant cobalt pregnant organic phase from the aqueous phase.

Abstract: A process for producing reagents useful in organic synthesis, for removing metal values from solutions thereof, for the capture of aldehydes, of the general formula ##STR1## wherein Z designates a recurring part (CH.sub.2 --CH--CH.sub.2 -- of a polymeric backbone of a polymer like polystyrene, of a copolymer comprising polystyrene and divinylbenzene, and butadiene, or other copolymers comprising styrene moieties; or wherein Z is the aliphatic moiety of a long-chain aralkyl compound having a terminal aryl group; or wherein Z designates alkyl; corresponding compounds wherein instead of the optionally substituted phenyl group there is present an optionally substituted naphthyl group; wherein n is an integer of from 1 to 15, and wherein Q designates a group selected from: ##STR2## wherein R designates --H, lower alkyl, aryl, which may be substituted and wherein R" designates --H, alkyl, aryl, halogen, nitro or carboxy, or ##STR3## wherein R is --H, lower alkyl, aryl (which may be substituted), R.sub.

Abstract: After the non-cobalt values are stripped from the co-loaded organic, the cobalt ions on the organic are reduced to the divalent state. The organic loaded with divalent cobalt ions is easily stripped with a dilute acid to render the organic recyclable.In another embodiment of the invention simultaneous reduction and "crowding" is utilized to strip cobalt from the organic. In this embodiment, a convenient source of both reductant Cu.sup.+ and of copper and/or nickel such as pregnant leach liquor is used to crowd the reduced cobalt from the organic.

Abstract: Production of titanium dioxide which is characterized by recovery of reusable H.sub.2 SO.sub.4, highly pure Fe oxide and hydroxide and fractional recovery of Mn, V and Cr, etc., from FeSO.sub.4. nH.sub.2 O and waste acid of 20 - 40% H.sub.2 SO.sub.4 containing abundant heavy metallic ions, which are by-produced in the production of TiO.sub.2 by dissolution of Ti raw materials such as ilmenite, steel production slag, such as electric furnace slag, convertor slag with H.sub.2 SO.sub.4.

Abstract: Cobalt, copper and nickel values are separated from ammoniacal aqueous solutions by contacting the solutions with a chelate exchange resin of polymerized ar-vinylbenzylamino dicarboxylic acids whereby the cobalt, copper and nickel values are loaded on the chelate exchange resin, stripping the cobalt, copper and nickel values from the loaded chelate exchange resin by contacting the loaded resin with a mineral acid and restoring the capacity of the chelate exchange resin when it falls below a predetermined value by reacting the degraded chelate exchange resin with an aqueous solution of a halo salt of a carboxylic acid, the aqueous solution being maintained at a pH value greater than about 8.

Abstract: A co-reagent system in the form of an admixture of a metal chelation collector and a mono- or dialkyl substituted phosphoric acid is adapted for selectively removing ferric iron from base metal electrolytic solutions in accordance with the liquid-liquid ion exchange extraction technique.

Abstract: Process of extracting metals using organic solvent solutions of salts of hydrogen ion exchange agents and quaternary ammonium compounds. Organic solvent solutions of such quaternary ammonium salts of hydrogen ion exchange agents.

Abstract: A process for the re-utilization of the sulphate residues from the electrolytic treatment of zinc.The residues are digested hot with concentrated HCl in the presence of CaCl.sub.2. PbCl.sub.2 crystallizes on cooling. FeCl.sub.3 is extracted with TBP circulating in the direction of a series of columns and FeCl.sub.3 is extracted in a first column, washed in a second column and re-extracted a third column. The solution which issues is treated with NH.sub.3, resulting in precipitation of the majority of the hydroxides of the metals contained therein, which are subsequently separated, while Ag, Zn and Cu are complexed. Ag is precipitated with (NH.sub.4).sub.2 S.NH.sub.3 is recovered by means of lime. CaCl.sub.2 is re-cycled to the start of the process and Cu and Zn are leached together with the mineral.Application of the process to the recovery of the metals contained in the residues from the digestion of blends.

Abstract: A method for the selective recovery of cadmium, nickel and cobalt from a nickel-cadmium battery waste which comprises:A. leaching the waste with an ammoniacal carbonate solution to form an aqueous ammoniacal carbonate solution containing cadmium, nickel and cobalt (II) ammine complexes and a leaching residue. Any iron in the waste is in the leaching residue.B. adding air to the aqueous ammoniacal carbonate solution to oxidize the cobalt (II) ammine complex to cobalt (III) ammine complex.C. contacting the resulting aqueous ammoniacal carbonate solution with a substantially water insoluble organic solution which contains a hydroxyoxime which forms a nickel compound readily soluble in the organic solution with any nickel present but which does not affect cadmium and cobalt (III). Nickel is thereby removed.D. precipitating the cadmium as a carbonate by removing ammonia from the aqueous ammoniacal carbonate solution and then removing the cadmium in the form of a carbonate.E.

Abstract: In this process metal ions such as Ag.sup.+, Pb.sup.2+, Co.sup.2+, Cu.sup. 2+, Fe.sup.3+, etc., are extracted through a porous membrane impregnated with the first extractant containing chelating agents. The membrane contacts with an extraction feed on one side, and with the second extractant on the other side, and the objective metal ions are transferred from the feed to the second extractant. Throughout the extraction process, the pH values of the extraction feed, the impregnated extractant solution, and the second extractant are kept in decreasing order.An apparatus used for the above objective is also provided by this invention.

Abstract: The present invention relates to a solvent extraction process for selectively recovering copper from an aqueous solution containing copper and nickel and having a pH above about 9. By employing only limited amounts of oxime, sufficient to provide about equivalent exchangeable hydrogen ion therein to latent copper ion of the aqueous stream, copper ion can be extracted in a multistage countercurrent process preferentially to nickel or cobalt. Hydrogen ion of the oxime molecule exchanges with copper ion in the aqueous solution in accordance with the equation:(2R.sup.o H)org. + (CU.sup.++)aqu. .fwdarw.(R.sub.2.sup.o Cu)org. + (2H).sup.+ aqu.wherein R.sup.o is the organic moiety of the oxime. The oxime selectively extracts copper when the mole ratio of exchangeable hydrogen ion of the oxime to copper ion in the aqueous is maintained between about 1.8 and 2.4.

Abstract: There is provided a cobalt ion exchange process for recovering cobalt from ammoniacal solutions comprising the steps of bringing the ammoniacal solution into contact with carbonaceous material, the redox potential of the solution being in the range +20 to -150 mV as measured by a platinum-calomel standard electrode pair, extracting the cobalt from the leach solution with a cationic ion exchange reagent, and recovering substantially all the cobalt from the ion exchange reagent by elution. The process of the invention enables cobalt to be removed from an ammoniacal leach solution which may also contain nickel and copper, in the form of a highly pure cobalt eluate.

Abstract: Ocean floor nodules are treated with halogenating agents to produce a pregnant leach solution which is subjected to selective solvent extraction to isolate metal values contained in the ore.

Abstract: Optionally substituted benzimidazoles containing an alkyl or cycloalkyl group in position 1 and containing at least 5 alkyl or cycloalkyl carbon atoms extract metals from aqueous solutions of their salts into water-immiscible organic solvents in presence of halide ion. Benzimidazoles having a branched-chain alkyl group of at least 7 carbon atoms in position 1, and especially mixtures of such compounds, are most effective. The benzimidazoles are particularly useful for extracting cobalt selectively from mixtures of cobalt and nickel salts. The metals can be recovered from the organic solvent by extraction into water free from halide ion.

Abstract: The ore is subjected to nitric acid leaching and the leach solution is heated to a temperature at which one of the additional sulfur and iron values is selectively insolubilized with respect to the solution, while the other is maintained in solution for subsequent separation from the liquor after the insolubles have been removed and the liquor has been neutralized. In addition, in one embodiment of the invention the heating and acid neutralization steps are controlled within certain prescribed limits to make it possible to remove the metals from the liquor by solvent extraction without the problem of lasting precipitates forming in the liquor and fouling the extraction process. Where there is a sizable amount of dissolved iron in the liquor, the liquor may be subjected to autoclaving at a temperature above about 149.degree. C (300.degree. F) to precipitate the iron as the oxide thereof. This effect is possible even where the liquor is high in sulfate concentration.

Abstract: A process for selectively removing ammonia from an organic solution containing ammonia and an oxime-metal chelate which comprises countercurrently contacting the organic solution with an aqueous solution of ammonium carbonate, ammonium bicarbonate, alkali metal bicarbonate or mixtures thereof. The mole ratio of ammonia, in organic solution prior to contact with the carbonate solution, to carbonate and/or bicarbonate in the fresh aqueous scrub solution is maintained so that ammonia transfer is effected from the organic solution to the aqueous solution. In the fresh scrub solution, the carbonate or bicarbonate concentration is maintained sufficiently high to prevent substantial emulsification of aqueous phase in the organic solution and the ammonia concentration is less than the ammonia concentration in equilibrium with 50 mg/l ammonia in the organic solution.

Abstract: Metal ions may be scavenged from solution by means of a complexing agent comprising an inorganic substrate, such as a clay mineral, with covalent organic molecules, such as onium compounds, chemically bonded to the substrate, the covalent organic molecules containing free coordinating groups. The complexing agents are particularly useful in scavenging environmentally harmful metal ions such as mercury from industrial effluents.