Abstract: Fine aluminum powders are prepared by decomposing alane-adducts in organic solvents under an inert atmosphere to provide highly uniform particles and believed particularly effective as fuels and additives, in pyrotechnics, and in energetic materials. Effective adduct species are trialkyl amines and tetramethylethylenediamine, ethers and other aromatic amines. Effective production is obtained at atmospheric pressure and at temperatures as low as 50° C. with xylene solvent. Toluene, dioxane, and tetramethylethylenediamine were also effective solvents. Aliphatic solvents and other aromatic and polar solvents are believed effective. Titanium catalyst was provided as a halide, amide, and alkoxide; and it is believed that the corresponding compounds of zirconium, hafnium, vanadium, niobium, and tantalum are effective as catalysts. Particle size was controlled by varying catalyst concentration and by varying the concentration of an adducting species.

Abstract: A method for dissociating metal-ligand complexes in a supercritical fluid by treating the metal-ligand complex with heat and/or reducing or oxidizing agents is described. Once the metal-ligand complex is dissociated, the resulting metal and/or metal oxide form fine particles of substantially uniform size. In preferred embodiments, the solvent is supercritical carbon dioxide and the ligand is a .beta.-diketone such as hexafluoroacetylacetone or dibutyldiacetate. In other preferred embodiments, the metals in the metal-ligand complex are copper, silver, gold, tungsten, titanium, tantalum, tin, or mixtures thereof. In preferred embodiments, the reducing agent is hydrogen. The method provides an efficient process for dissociating metal-ligand complexes and produces easily-collected metal particles free from hydrocarbon solvent impurities. The ligand and the supercritical fluid can be regenerated to provide an economic, efficient process.

Abstract: Fine aluminum powders are prepared by decomposing alane-adducts in organic olvents under an inert atmosphere to provide highly uniform particles and believed particularly effective as fuels and additives, in pyrotechnics, and in energetic materials. Effective adduct species are trialkyl amines and tetramethylethylenediamine, ethers and other aromatic amines. Effective production is obtained at atmospheric pressure and at temperatures as low as 50.degree. C. with xylene solvent. Toluene, dioxane, and tetramethylethylenediamine were also effective solvents. Aliphatic solvents and other aromatic and polar solvents are believed effective. Titanium catalyst was provided as a halide, amide, and alkoxide; and it is believed that the corresponding compounds of zirconium, hafnium, vanadium, niobium, and tantalum are effective as catalysts. Particle size was controlled by varying catalyst concentration and by varying the concentration of an adducting species.

Abstract: Fine aluminum powders are prepared by decomposing alane-adducts in organic solvents under an inert atmosphere to provide highly uniform particles selectably sized from about 65 nm to about 500 nm and believed particularly effective as fuels and additives, in pyrotechnics, and in energetic materials including composites, super thermite, and other explosives. Effective adduct species are trialkyl amines and tetramethylethylenediamine, ethers and other aromatic amines being believed effective. Effective production is obtained at atmospheric pressure and at temperatures as low as 50.degree. C. with xylene solvent. Increased production rate is achieved at higher temperatures. Toluene, dioxane, and tetramethylethylenediamine were also effective solvents. Aliphatic solvents and other aromatic and polar solvents are believed effective.

Abstract: There is provided a process for converting a silver-mercapto-s-triazine precipitate to a solid containing silver and a solution containing mercapto-s-triazine by contacting the silver-mercapto-s-triazine precipitate with one or more reducing agents. In preferred embodiments, at least one of the reducing agents has a redox potential more negative than about -0.9 V vs. Normal Hydrogen Electrode, NHE.

Abstract: Spent solutions from photographic processors are fed into a conduit (18) to which subsequently are added precipitating agents from a first source (22) and flocculating agents from a second source (28); so that, well grown or ripened clumps of flocculated solids are formed along the conduit before being emptied into a gravity collecting vessel and shipping container (38) from which clarified liquids are displaced by a mass (50) of accumulated flocculated solids, typically through a filter (58, 142, 150, 158, 162, 166, 220)for removal of any unsettled fines. Many of the clumps of flocculated solids become enlarged enough to individually extend across and substantially fill a cross-sectional area of the conduit. As a result, the enlarged clumps substantially block passage of and strain from the solution remaining fine particles which then adhere to the clumps.

Abstract: An improved process for dissolving gold metal in ligand and oxidant lixiviation systems, wherein the solubility of gold is enhanced by the addition of heterocyclic aromatic compounds containing nitrogen or sulfur in the ring.

Abstract: A method for the separation of rhodium and/or iridium from a solution containing ruthenium said method comprising the steps of having a rhodium chloride complex in oxidation state III, converting the ruthenium to nitrosyl complexes in divalent states and recovering rhodium and/or iridium.

Abstract: A process for producing finely divided 20 to 500 angstrom metal particles, metals with oxide coatings or metal oxides using an alkalide or electride in a non-reactive solvent is described. The process produces various forms of the metal depending upon the oxidizability of the metal initially produced by the process. The process is useful for producing catalysts, alloys, colloidal solutions, semi-conductors and the like.

Abstract: The invention provides a hydrometallurgical process for the recovery of metals. In particular, an aqueous feed solution originating from acid leaching is provided. The aqueous feed solution contains nickel and/or cobalt ions. The pH of the solution is maintained at a level between about 2 and 6. The aqueous feed solution is contacted with a water-immiscible organic phase containing an extractant to load the nickel and/or cobalt metal ions to form a metal-bearing organic phase. The extractant has at least one organic soluble dithiophosphinic acid, alkali, alkaline earth metal or ammonium salt thereof. The aqueous feed solution has sufficiently low levels of chromium (VI) ions, iron (III) ions and copper ions to allow repeated use of the extractant. The metal-bearing organic phase is then separated from the metal-containing aqueous feed solution.

Abstract: A process for extracting metal values especially zinc values from aqueous solutions of metal salts which comprises contacting the aqueous solution with an organic phase comprising a compound of the formula: ##STR1## wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4, independently, represents an optionally substituted hydrocarbyl or hydrocarbyloxy group or R.sup.1 and R.sup.2 together with the attached phosphorus atom and/or R.sup.3 and R.sup.4 together with the attached phosphorus atom form a 5- to 8-membered heterocyclic ring.

Abstract: An efficient method is proposed for the recovery of gold value contained in an aqueous solution even in a very low concentration of the ppb level. Namely, an aqueous acidic solution containing gold value in the form of complex gold anions, e.g., chloro complex anions of gold, is contacted with a solid ion exchanger which is prepared by the adsorption of a 2-hydroxyethyl tri(C.sub.8-12)alkyl ammonium halide on porous resin beads of a polymer of methacrylic acid ester so that the complex gold anions are adsorbed by the ion exchange reaction to form ion pairs with the quaternary ammonium cations. The thus adsorbed complex gold anions coupled with the quaternary ammonium cations can be eluted out of the adsorbent with an organic solvent such as alcohols and ketones in a quantitative yield of recovery.

Abstract: A precipitating agent containing thioacetamide is described for the precipitating of heavy metals from flue gases and waste waters, it containing thioacetamide (C.sub.2 H.sub.5 SN) in a 1-20% aqueous solution, which, in addition, contains a buffer substance in order to prevent hydrolyric spontaneous decomposition, the solution having a pH of between 5.5 and 9.0.

Abstract: A method for the removal, separation, and concentration of alkali metal, alkaline earth metal, Pb and/or Tl cations from a source solution which may contain larger concentrations of other ions comprises bringing the source solution into contact with a compound comprising an oxygen donor macrocycle-containing ligand covalently bonded through an organic spacer silicon grouping to a solid inorganic support. The ligand portion(s) of the compound has affinity for alkali metal, alkaline earth metal, Pb and/or Tl thereby removing them from the source solution. The alkali metal, alkaline earth metal, Pb and/or Tl cations are then removed from the compound through contact with a much smaller volume of a receiving solution in which these cations are either soluble or which has greater affinity for such cations than does the oxygen donor macrocyclic ligand thereby quantitatively stripping the complexed cations from the ligand and recovering them in concentrated form in said receiving solution.

Abstract: An efficient method is proposed for the recovery of gold value from a waste material containing scrap gold by utilizing a principle that metallic gold can be dissolved at elevated temperatures and specifically precipitated at low temperatures with good reversibility in and out of a specific unique liquid medium which is an organic solvent, e.g., acetonitrile, containing an ionic compound of a first halogen, e.g., quaternary ammonium halides, and an elementary form of a second halogen each in a specified concentration, of which at least either one of the first and second halogens is iodine. Namely, a gold-containing waste material is contacted at a high temperature with the liquid medium to have the gold value dissolved therein and the gold-containing solution is then cooled to a low temperature so that the gold value can be recovered in the form of precipitates in a high purity.

Abstract: The invention provides a hydrometallurgical process for the recovery of metals. In particular, an aqueous feed solution derived from acid leaching is provided. The aqueous feed solution contains nickel and/or cobalt ions. The pH of the solution is maintained at a level between about 2 and 6. The aqueous feed solution is contacted with a water-immiscible organic phase containing an extractant to load the nickel and/or cobalt metal ions to form a metal-bearing organic phase. The extractant has at least one organic soluble dithiophosphinic acid, alkali, alkaline earth metal or ammonium salt thereof. The aqueous feed solution has sufficiently low levels of chromium (VI) ions and copper ions to allow repeated use of the extractant. The metal-bearing organic phase is then separated from the metal-containing aqueous feed solution.

Abstract: A process for the passivation of fine particulate matter exiting a reactor train for the manufacture of organohalosilanes comprising treating the particulate matter or fines with an aqueous medium comprising a polyalkylene ether surfactant and optionally an acidifying agent to produce hydrogen, separating the fines from the aqueous medium, and removing water from the fines.

Abstract: A method for the recovery of a metal from an organic complex thereof, said method comprising treating the complex with a weakly acid aqueous solution of an alkali metal or alkaline earth metal chloride having a chloride content of at least 4 molar whereby said complex is decomposed and metal ions are transferred to the aqueous solution.

Abstract: A process for the separation of rhodium from rhodium containing organic solutions, organic-aqueous mixtures or aqueous solutions containing complexing agents is disclosed. Metallic bismuth, bismuth oxide, bismuth hydroxide or another reducible bismuth compound is added to 50.degree. to 250.degree. C. as a precipitating agent, optionally with a reducing agent, and the precipitate is separated. The corresponding antimony compounds can also be used in place of bismuth.

Abstract: A process for the production of a fine powder suitable for use in the fields of electronic materials, catalysts, powder metallurgy, pigments and adsorbens. The powder has a primary particle diameter of not more than 0.5 .mu.m, an average secondary aggregate particle diameter of not more than 10 .mu.m and a secondary aggregate particle specific surface area of 2 to 250 m.sup.2 /g, and is produced by a process comprising heating an organic acid metal salt in the presence of palladium, which lowers the thermal decomposition temperature of the salt, at a temperature elevation rate of 0.5.degree. to 20.degree.C./minute and thermally decomposing the organic acid metal salt in the presence of the palladium in the temperature range of not higher than 400.degree.C.

Abstract: Aqueous solutions containing metal cations, that may include cations of both desired metal and impurity or secondary metal, are treated with an organic liquid extractant suitable for the extraction of cations of the desired metal, cations of at least one secondary metal being co-extracted. After phase disengagement, the loaded organic phase containing cations of either a desired metal or desired metal together with at least one secondary metal is contacted with a solid metal or solid metal alloy capable of reducing in the organic phase cations of either a desired metal or a secondary metal from a higher to a lower state of oxidation. Depending on the extracted metal(s) and the added solid metal or alloy, cations of the at least one extracted metal are reduced to the lower state of oxidation and either are deposited (cemented) in the metallic state onto the solid metal or alloy, or are partially reduced in the organic phase to a lower oxidation state with the solid metal or alloy being oxidized in part.

Abstract: A process for extracting gallium from an aqueous gallium-bearing acidic solution comprises: a) providing a quantity of phosphorus within the aqueous gallium-bearing solution, the phosphorus being provided in an aqueous soluble form and being substantially dissolved within the aqueous solution, the aqueous gallium-bearing solution having dissolved phosphorus defining a first aqueous phase; b) intermixing the aqueous gallium-bearing solution having the quantity of aqueous soluble dissolved phosphorus with a first organic phase comprising a quantity of an alkylated 8-hydroxyquinoline; c) separating the intermixed first aqueous phase and first organic phases into a second aqueous phase and a second organic phase, the quantities of aqueous soluble phosphorus and alkylated 8-hydroxyquinoline being effective to extract gallium from the aqueous gallium-bearing solution to provide a gallium concentration in the second organic phase which is greater than a gallium concentration in the first organic phase and to provide

Abstract: From an ore containing gold and silver, the gold and silver are extracted by a method which comprises pulverizing the ore and bringing the pulverized ore into contact with an elemental halogen, a halogenated salt, and an organic solvent thereby converting the gold and silver into polyhalogeno anionic complexes and consequently dissolving them in the organic solvent.

Abstract: A mixture of cyanide complexes with certain Group VIII metals and other metals is passed in contact with solid subdivided cross-linked polyvinylpyrrolidone whereby the Group VIII metals--platinum, palladium, rhodium and iridium--are preferentially retained on the cross-linked polyvinylpyrrolidone. The retained metals are recovered by ashing or chemical treatment of the cross-linked polyvinylpyrrolidone.

Abstract: A method for recovering a transition metal such as rhodium from a polar or non-polar liquid by contacting said transition metal-containing liquid with an ion-exchange resin having bonded ionically thereto an organophosphorus ligand; the transition metal can be eluted from the bed using a liquid containing a sufficient concentration of organophosphorus ligand.

Abstract: There are provided novel compounds useful as selective extractants of metal values from aqueous systems comprising a plurality of such ionic species. There is further provided a process for the production of the novel compounds. The invention also relates to a process of selective metal extraction by means of the novel compounds of the invention.

Abstract: There is disclosed a method for the separation of antimony from acidic solutions which contain antimony, alone, or together with other metallic ions, by extracting antimony with an organic, water-immiscible, polyol-containing diluent. The method comprises the steps of contacting the antimony-containing acidic solution with a water-immiscible organic diluent containing at least one polyol dissolved therein, preferably a diol, said polyol serving to extract the antimony. The polyol serves to selectively extract the antimony from the acidic solution to the exclusion of other metallic ions such as copper and nickel.

Abstract: The present invention provides a process for the passivation of pyrophoric metals and especially of magnesium by coating with a passivation agent, wherein, as passivation agent, there is used 0.5 to 5% by weight of an s-triazine derivative and/or a guanidine, referred to the weight of the metal.The present invention also provides a passivated pyrophoric metal, wherein the metal particles are coated with 0.5 to 5% by weight of an s-triazine derivative and/or guanidine or a guanidine derivative, referred to the weight of the metal.

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: A process for extracting metal values such as gallium and/or indium from aqueous solutions by contacting said solutions with a water immiscible organic solvent having dissolved therein a heterocyclic thione.

Abstract: A process for the removal of cadmium ions by liquid-liquid extraction from wet process phosphoric acid, which had been obtained from crude phosphate ores by dissolution with sulfuric acid, uses salts of long chain alkyl amines or ammonium bases with the chlorocomplexes of polyvalent metal ions, which are dissolved in an inert organic solvent.

Abstract: A process for recovery of platinum and palladium from an impure substantially gold-free precious and base metal-bearing acidic chloride or mixed chloride/sulphate solution comprises the steps of: contacting the acidic solution having a pH less than about 1.5 with an organic solution comprising an 8-hydroxy quinoline solvent extraction reagent, a phase modifier and an aromatic diluent to extract simultaneously platinum and palladium into the organic solution; scrubbing the loaded organic solution to remove co-extracted impurities and acid; stripping the loaded organic with a buffer solution operating in the pH range 2-5 at 20.degree.-50.degree. C. to selectively recover the platinum; stripping the platinum-free loaded organic with 3-8 M hydrochloric acid to recover the palladium; and regenerating the organic solution by washing with water.

Abstract: Prior art processes for removal of one or more contaminant elements, including at least one of antimony, bismuth, and arsenic and optionally including iron, from electrolyte solutions of primary metals by solvent extraction with an organic phase including a hydroxamic acid, then precipitating at least part of the contaminant elements from the organic phase as sulfides, are improved by an additional step of re-extracting the organic phase with water before precipitating the sulfides from it. At least part of any arsenic present and, if desired, part of any antimony as well, may be re-extracted in this manner and subsequently recovered if desired, so that the overall process is made more economical.

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: An improved process for recovery for precious metals such as gold and silver from aqueous cyanide solutions by contact with certain guanidine reagents. The guanidine reagents not only extract the precious metal but may provide advantages in selectivity of gold over other metals, such as tetra- and pentahydrocarbon substituted non-resin guanidine reagents and tri- and tetra-hydrocarbon substituted resin guanidine reagents.

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: A relatively solid, stable biomass reaction product is provided produced from microorganisms having metal uptake properties when contacted by an aqueous solution containing metal cations. The biomass reaction product is produced by treating cells thereof with a caustic solution, whereby the biomass reaction product after drying is characterized in the particulate state of having substantially enhanced uptake of metal cations from aqueous solutions as compared to the metal uptake property of the microorganism before treatment. The biomass reaction product in the particulate state is preferably immobilized in an insoluble binder.

Abstract: A method of treating a gold-bearing ore to render the gold component of the ore more amenable to standard cyanidation treatment in a reduced amount of time is disclosed. An aqueous slurry of the gold-bearing ore is introduced into at least one vessel. An oxidizing agent, such as chlorine gas, an alkali metal hypochlorite and an alkaline earth metal hypochlorite, is rapidly introduced into the vessel so that it intimately contacts the aqueous slurry. While the oxidizing agent is being introduced into the vessel, the slurry is agitated with agitating means including a plurality of impeller blades that provide high shear agitation and a large interfacial surface area between the oxidizing agent and the liquid phase of the slurry to enhance the mass transfer of the oxidizing agent so that it becomes substantially completely adsorbed by the aqueous slurry in about 5 to about 15 minutes.

Abstract: Process for recovering gold from a leachate containing AuBr.sub.4.sup.-- comprising contacting the leachate with a quantity of sphagnum peat moss under conditions effective to concentrate the gold on the moss, and thereafter recovering the gold from the sphagnum peat moss.

Abstract: Heap leaching of gold/silver ores with an aqueous alkali cyanide solution containing a surfactant hydrolyzable at the pH of the solution, the surfactant being present in an amount sufficient to increase the rate of metal value recovery without adversely affecting the carbon efficiency in the subsequent step of separating the metal cyanide value from the pregnant leach solution by absorption on carbon columns.

Abstract: A method for the recovery of a metal from an organic complex thereof, said method comprising treating the complex with a weakly acid aqueous solution of an alkali metal or alkaline earth metal chloride having a chloride content of at least 4 molar whereby said complex is decomposed and metal ions are transferred to the aqueous solution.

Abstract: A method for the recovery of a metal from an organic complex thereof, said method comprising treating the complex with a weakly acid aqueous solution of an alkali metal, an alkaline earth metal or ammonium chloride having a chloride content of at least 4 molar whereby said complex is decomposed and metal ions are transferred to the aqueous solution.