Abstract: A solvent extraction process is provided for transferring metal values from one immiscible liquid phase to another, whereby the two liquid phases are vigorously mixed together in a first mixer under conditions in which one liquid phase is rendered continuous, the mixing being continued to effect complete transfer of metal values, and the mixture then passed to a second mixer and the two phases mixed under conditions in which the other phase is rendered continuous, whereby when the two phases are fed to a settler, the rate of disengagement of the two immiscible liquids is substantially increased.

Abstract: Processes are described for preparing pure ammonium molybdate from impure roasted molybdenum concentrates. An aqueous solution of nitric acid and ammonium nitrate is contacted with impure molybdenum concentrate to solubilize a major portion of the impurities. The resulting molybdenum concentrate is digested in ammonium hydroxide under conditions that maximize iron precipitation and removal. The resulting ammonium molybdate solution is separated from the sludge and further purified by chelating cation exchange resin in the ammonium form.

Abstract: A process for removing metal contaminants from a hydroconversion catalyst, said catalyst containing at least one metal from Groups VIB, VIIB or VIII supported on a refractory inorganic oxide. The process comprises contacting the contaminated catalyst with a buffered oxalic acid solution wherein contaminant is removed without dissolving the support.

Abstract: In a process is disclosed for recovering rhenium from tungsten and rhenium bearing material by oxidizing and fusing the starting material, solubilizing the tungsten and rhenium values, passing the resulting solution through a strongly basic anion exchange resin to retain the rhenium, removing the rhenium from the resin with an organic stripping liquid of tributylphosphate and hydrochloric acid, washing the remaining rhenium off the resin with water, combining the water and organic to form a two phase system in which the organic phase contains the major portion of the rhenium, and contacting with aqueous ammonia to strip values.

Abstract: A method of stripping an organic extraction solvent containing quaternary alkyl ammonium complexes. The extraction solvent is contacted with an aqueous stripping solution having at least 75 g/l bicarbonate ion, while maintained at between pH 7 and 9 at a temperature of no more than 50.degree. C.

Abstract: A process for the recovery of molybdenum and/or tungsten from a solution which comprises the steps of passing said solution through a packed column containing an adsorbent; adsorbing tungsten and/or molybdenum on said adsorbent; passing a solution depleted in tungsten and/or molybdenum from said column; passing a stripping solution through said column containing tungsten and/or molybdenum on said adsorbent to remove tungsten and/or molybdenum with said stripping solution; repeating the first four steps until the stripping solution contains at least about 1 gram per liter of tungsten and/or molybdenum; passing said solution containing at least about 1 gram of tungsten and/or molybdenum per liter into a recovery zone; adjusting the pH of said stripping solution containing at least about 1 gram per liter of tungsten and/or molybdenum to approximately 13.0 by addition of a strong acid and thereby raising the temperature of said solution at least about 10.degree. C.

Abstract: A method of recovering metal values from an aqueous stream. The metal values are preferably obtained from leaching spent hydroprocessing catalysts, and include nickel, cobalt, vanadium and molybdenum. The metal values are extracted, isolated and purified by liquid, liquid extraction techniques.

Abstract: A process for removing nickel, cobalt, molybdenum, and vanadium from spent hydroprocessing catalyst particles by roasting the catalyst at between 400.degree. C. and 600.degree. C. and leaching the catalyst particles with an aqueous solution of ammonia and an ammonium salt.

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: A spent or scrap tungsten-containing, aluminosilicate catalyst material is blended with a silicate-containing, tungsten-bearing ore concentrate in amounts such that at least about 2.0% by weight of the total tungsten values in the mixture are present in the catalyst material, and then digested with an alkaline solution, e.g., sodium carbonate, under pressure and at an elevated temperature for a period of time sufficient to extract substantially all of the tungsten values from the mixture components. The presence of the catalyst material substantially suppresses the dissolution of silica in the leach liquor.

Abstract: Foaming in the hydrometallurgical treatment of a tungsten-containing aqueous solution due to the presence of carbonaceous organic material impurities, such as flotation reagents, is substantially inhibited by the addition of effective amounts of powdered activated carbon, the carbon with the adsorbed impurities being thereafter separated from the solution by filtering. The activated carbon also protects the solvent extraction circuit from contamination. The method is particularly applicable to slurries of tungsten oxide concentrates during the high temperature, high pressure leaching thereof with sodium carbonate solutions in an autoclave.

Abstract: A process for recovering the metal values from spent hydroprocessing catalyst particles. The metal values will include at least one metal of Group VIII of the Periodic Table and at least one metal of Group Vb or Group VIb of the Periodic Table. The spent catalyst particles are first roasted at between 400.degree. C. and 600.degree. C. and then contacted with a first aqueous solution of ammonia and an ammonium salt forming a first pregnant liquor. The once-leached spent hydroprocessing catalysts are contacted with a second aqueous solution of sulfur dioxide forming a second pregnant liquor. The metal values are precipitated from the second pregnant liquor with hydrogen sulfide and the precipitate is roasted with unroasted spent hydroprocessing catalysts. The metal values of Group Vb and Group VIb in the first pregnant liquor are transferred into a first organic solution by liquid ion exchange.

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.

Abstract: A process is provided for recovering metal values from spent hydrodesulfurization catalyst, the process comprising forming in a pressure reactor an aqueous slurry of finely divided spent catalyst and sodium carbonate, the spent catalyst containing by weight about 2 to 10% Mo, up to about 12% V (e.g., about 2 to 10%), about 0.5 to 4% Co, up to about 10% Ni (e.g., about 0.5 to 5%), occluded oil, coke, sulfide sulfur and the balance essentially alumina. The amount of sodium carbonate employed is at least sufficient under oxidizing conditions to convert molybdenum and any vanadium present to soluble Na.sub.2 MoO.sub.4 and NaVO.sub.3 and to neutralize SO.sub.3 produced during oxidation, the amount of sodium carbonate being at least that required stoichiometrically. The slurry is heated to a temperature of about 200.degree. C. to 350.degree. C. (e.g., 275.degree. C. to 325.degree. C.) and a pressure of about 800 psig to 2500 psig (e.g.

Abstract: A process for separating trivalent iron from an aqueous chloride solution comprising contacting the aqueous solution with an organic phase containing an organophosphoric compound as an extracting agent for trivalent iron and at least 40 percent in volume of a long chain aliphatic alcohol, separating the iron-loaded organic phase from the aqueous solution, and re-extractng the iron from the iron-loaded organic phase by contacting the latter with water or acidulated water so as to produce an aqueous iron chloride solution.Owing to the high alcohol content of the organic phase, iron can be re-extracted with a small amount of water.

Abstract: Low grade copper concentrates containing molybdenum are roasted under conditions to form copper and molybdenum compounds which are soluble in dilute sulfuric acid solutions.Molybdenum is then recovered by solvent extraction from these solutions and further precipitated as ammonium molybdate, while copper can be electrowinned or precipitated from the raffinate.Overall recovery efficiencies are 96% for copper and 84% for molybdenum.

Abstract: A process for recovery of vanadium and molybdenum from a feed material containing compounds of these metals by reacting at an effective pH an aqueous solution of vanadate and molybdate anions with a quaternary ammonium surfactant dissolved in an organic solvent which is immiscible with water and separating a vanadate anion rich phase from a molybdate anion rich phase.

Abstract: A process for the recovery of valuable metals from metallic alloys having iron as their principal constituent is disclosed in which the metal is leached by means of a sulfuric acid solution having such a concentration that a nearly saturated salt solution is obtained, and after the separation of a possible leach residue the solution is heated close to the boiling point, at which time an acid solution is added in an amount corresponding to the salt which has passed out of the solution, in order to crystallize the salt mixture, the crystallized material is separated from the solution and is decomposed under sulfating conditions, whereafter the metal salts are leached out from the iron oxide by means of water.

Abstract: A process for treating a hydrometallurgical suspension resulting from the acid attack on an ore containing at least one metal element to be put to use, and non-attackable mineral materials, a fraction of which is formed of clays, comprising extracting the useful metal element which has gone into solution in the attack operation, by means of an organic solvent belonging to the group of alkyl phosphates, which is characterized by introducing a condensed mineral phosphate into the ore attack medium, for the purpose of limiting the losses due to adsorption of the organic extraction solvent by the clays.The process applies more particularly to uraniferous, molybdeniferous, vanadiferous and cobaltiferous ores.

Abstract: A process for stripping tungsten values from a tungsten-bearing acidic liquid organic phase into a basic aqueous ammoniacal stripping solution comprises mixing the organic phase and the stripping solution with a high-shear mixing device to maximize the pH gradient between the organic phase and the aqueous solution whereby growth of any precipitated ammonium paratungstate crystals is minimized and the dissolution thereof is maximized and to strip the tungsten values from the organic phase into the stripping solution.

Abstract: In a process for producing pure ammonium paratungstate from ammonium tungstate solutions containing tin, sulfide is added to the ammonium tungstate solution in an amount sufficient to form a soluble complex of the sulfide with the tin. The solution is then evaporated to a volume at which essentially all of the tungsten is in the form of insoluble ammonium paratungstate and essentially all of the tin is in the mother liquor in the form of a soluble complex along with other impurities. The solid ammonium paratungstate is then separated from the mother liquor by filtration.

Abstract: The invention relates to a process and a solvent for extraction of the chromates present in an aqueous solution. According to the invention, the aqueous phase is brought into contact with an organic phase comprising 2 to 10% by volume of a solvent selected from the group of tertiary or quaternary amines and 15 to 40% of a solvent selected from the group of esters of phosphoric acid in a diluent based on petroleum hydrocarbons. The invention is applicable to the production of concentrated solutions of chromates easily recyclable from an extraction of the chromates contained in an industrial solution.

Abstract: A hydrometallurgical process is provided for the recovery of molybdenum values from a molybdenum disulfide concentrate containing copper. The process comprises forming an aqueous slurry of finely divided molybdenum concentrate of carbonates and hydroxides of alkali metals, and pressure leaching the slurry in the presence of oxygen at an elevated temperature and pressure for a time sufficient to effect conversion of the contained molybdenum values to alkali metal molybdate and provide a residue containing copper oxide or basic copper carbonate from which copper is later recovered. The molybdenum values are recovered from solution by solvent extraction and the solvent thereafter stripped of the molybdenum as ammonium molybdenum using ammonium hydroxide. The molybdenum is recovered as crystals of ammonium molybdate by crystallization, e.g., by evaporating the stripping solution.

Abstract: A method for the removal of molybdenum from solutions containing molybdenum and other mineral values such as tungsten is accomplished by mixing the leachate solution with hydrogen peroxide to form a feed solution; the feed solution is contacted with a porous membrane, the opposite side of which is continuously contacted with an organic solution containing tributylphosphate. Additionally, for recovery of molybdenum, the tributylphosphate solution is additionally contacted with a second membrane the opposite side of which is contacted with a stripping solution such as a solution of sodium hydroxide or sodium carbonate. In a continuous ion exchange embodiment, the organic solution containing tributylphosphate is recirculated to contact the second side of the first membrane, preferably after passage through an aqueous separator.

Abstract: A method for recovering superalloy scrap is disclosed. The method involves oxidizing superalloy scrap in an aqueous acidic medium. The aqueous acidic medium has an oxidation potential sufficient to oxidize nonferrous additive superalloy elements to insoluble oxides thereof and to oxidize major superalloy constituents to aqueously soluble species. The insoluble solids from the aqueous solution are separated when the aqueous solution is extracted with an aqueously substantially insoluble tertiary amine to form an organic phase and an aqueous phase. The aqueous phase contains essentially nickel and chromium values. The organic phase is sequentially extracted with aqueous solutions which selectively solubilize individual metal value species to form individual aqueous solutions having substantially single metal value species therein. The metal value species solutions are processed to obtain substantially pure metals.

Abstract: A method of recovering metal values from an aqueous stream. The metal valves are preferably obtained from leaching spent hydroprocessing catalysts, and include cobalt, nickel, molybdenum and vanadium. The metal values are extracted, isolated, and purified by liquid extraction techniques.

Abstract: This invention concerns a process for extracting chromium (III) from an aqueous solution containing chromium (III) with an extractant comprising a mixture of mono-2-ethylhexyl phosphoric acid and di-2-ethylhexyl phosphoric acid. An organic solvent such as a low aromatic kerosene is employed in this invention for dilution and dissolution of the extractant. Aqueous acid waste streams containing chromium (III) can be reduced to a chromium (III) concentration of 80 ppm thereby enabling the stream to be reclaimed.

Abstract: A method of recovering metal values from an aqueous stream. The metal values are preferably obtained from leaching spent hydroprocessing catalysts, and include nickel, cobalt, vanadium and molybdenum. The metal values are extracted, isolated and purified by liquid, liquid extraction techniques.

Abstract: A method of stripping an organic extraction solvent containing quaternary alkyl ammonium complexes. The extraction solvent is contacted with an aqueous stripping solution having at least 75 g/l bicarbonate ion, while maintained at between pH 7 and 9 at a temperature of no more than 50.degree. C.

Abstract: A process for separating metal values from an aqueous stream containing vanadium, molybdenum, nickel and cobalt. Vanadium is first precipitated, and then nickel, cobalt, and molybdenum are removed by serial ion exchange.

Abstract: The phenolic chelate resin has a chelate-forming group wherein part or all of the hydrogen atoms in a primary and/or secondary alkylamino group introduced in a phenol nucleus are replaced by a methylenephosphonate group. Also disclosed is a process for producing such a chelate resin, and a method for recovering heavy metal ions with such a resin. The resin has particularly high selectivity for adsorbing uranium ions, as well as high heat, acid and alkali resistance as well as dimensional stability. The resin is very effective for recovering uranium from various uranium-containing solutions such as sea water, crude phosphoric acid fertilizer solutions, low-grade uranium ore, waste water from uranium refining, and uranium mine water.

Abstract: Tungsten is recovered from alkaline brines by: (1) initial loading of metal values on an 8-hydroxyquinoline-resorcinol-formaldehyde resin, (2) selective desorption of boron, arsenic and sulfur from the resin by means of an NH.sub.4 Cl--NH.sub.4 OH solution having a pH of about 7.5 to 9.5, and (3) desorption of tungsten from the resin by means of water or an alkaline solution.

Abstract: A modified liquid-liquid extraction system is disclosed in which a particulate solid and a liquid, both insoluble in a second liquid, are mixed to form agglomerate particles which efficiently extract metal ions from dilute solutions. The extraction is rapid and requires a much lower volume of extracting phase for good contacting than conventional liquid-liquid extraction. Mixing energy is low, clean-up of effluent water is easily accomplished and metal values are readily stripped from the agglomerates by well-known techniques, such as treatment by aqueous acid solution.

Abstract: Molybdenum catalyst employed in the epoxidation of an olefin with an organic hydroperoxide preferably the epoxidation of propylene, is recovered from the bottoms fraction by adding aqueous alkaline material to the bottoms fraction and separating the aqueous phase. The molybdenum can be recovered from the aqueous phase by acidification and precipitating it as an insoluble compound.

Abstract: A process for recovering uranium values from a sulphate solution containing dissolved uranium and molybdenum and with a pH not exceeding about 5.5, includes reacting the solution with ammonia at a pH in the range of from about 8 to about 10, without the solution existing for any significant time at a pH of around 7, with resultant precipitation of uranium values relatively uncontaminated by molybdenum. The uranium containing precipitate is separated from the remaining solution while maintaining the pH of the remaining solution within the same range.

Abstract: Recovery of molybdenum from a solid mixture, such as an exhausted catalyst, containing molybdenum in the oxide form or in the form of molybdic ions and other metallic compounds.The mixture is contacted with an aqueous alkali metal hydroxide to solubilize molybdenum in the form of an alkali metal molybdate, and after filtration the aqueous solution of alkali metal molybdate thus obtained is contacted with a strong cationic exchange resin to convert said molybdate into molybdic acid.

Abstract: The instant invention relates to a process for removing tungsten, and/or molybdenum generally, as the tungstate and/or the molybdate anion, from aqueous solutions, e.g. brines by contacting such solutions with a high-surface area oxide selected from the group consisting of manganese and iron oxides, preferably manganese or iron hydrous oxide, whereby tungsten or molybdenum is adsorbed on said high-surface area oxide. The instant process provides selectivity for tungsten as well as molybdenum even though they are present in solutions containing various other materials such as sodium, potassium, calcium, etc. ions. This process is preferably applicable to removal of tungsten from high pH brines such as a brine having a pH of at least 9, for example greater than 10. The oxide adsorbent may be regenerated by contacting with an aqueous solution having a pH higher than the brine from which the tungsten and/or the molybdenum has been removed.

Abstract: The phenolic chelate resin has a chelate-forming group wherein part or all of the hydrogen atoms in a primary and/or secondary alkylamino group introduced in a phenol nucleus are replaced by a methylenephosphonate group. Also disclosed is a process for producing such a chelate resin, and a method for recovering heavy metal ions with such a resin. The resin has particularly high selectivity for adsorbing uranium ions, as well as high heat, acid and alkali resistance as well as dimensional stability. The resin is very effective for recovering uranium from various uranium-containing solutions such as sea water, crude phosphoric acid fertilizer solutions, lowgrade uranium ore, waste water from uranium refining, and uranium mine water.

Abstract: The present invention relates to a process for the selective separation of uranium and molybdenum which are contained in an extract resulting from an amino solvent liquid-liquid extraction of a solution resulting from an attack on a molybdo-uraniferous ore by means of sulphuric acid, and which comprises re-extraction of the uranium in the presence of an oxidizing agent by means of an acid solution of an alkali metal chloride, followed by re-extraction of the molybdenum by means of an alkali metal carbonate solution. This process is characterized by using an oxidizing agent such as hydrogen peroxide, a small amount of which is added to the acid alkali metal chloride solution before the latter is brought into contact with the extract. This makes it possible to achieve selective separation of the uranium and molybdenum.

Abstract: In a continuous process for producing ammonium tungstate from aqueous alkali metal tungstate solution according to an extraction process, the loaded organic extractant is cleaned after stripping by contacting with activated carbon for improving phase separation and decreasing the concentration of alkali metal.

Abstract: In the removal of chromium and zinc, the combination of an anion exchange resin and cation exchange resin in a single vessel, the anion exchange resin being selective of chromium in its chromate and dichromate ionic forms, and the cation exchange resin being an intermediate acid cation exchange resin with a phosphonic acid functional group on a cross-linked polystyrene matrix, having the repeating structural formula: ##STR1## selective of zinc in its ionic form, said single vessel, having distributors selected from the group of inlet distributors, regenerant distributors, subsurface washers, collectors, disposed therein, and inlets and outlets for the addition or removal of effluent, water and regenerant.

Abstract: From a chlorate cell liquor containing an alkali metal chlorate, an alkali metal chloride and Cr(VI) ions, Cr(VI) ions are recovered by means of a combination of simple chemical procedures and re-used in an electrolysis step for manufacturing an alkali metal chlorate.

Abstract: A process is described for recovering uranium from a pregnant lixiviant containing uranium values and a certain portion of molybdenum values comprising passing the pregnant lixiviant through an anion-exchange resin to capture the uranium and molybdenum values on the resin, eluting the uranium and molybdenum values from the resin with a salt solution, passing the eluate through a weak acid cationic resin in its hydrogen form to capture the uranium values on the resin and treating and resulting eluate to precipitate uranium therefrom to produce the familiar "yellow-cake.

Abstract: Molybdenum is removed from an aqueous solution containing tungsten and molybdenum by extracting the molybdenum from the aqueous solution having a pH greater than 8.5 with a liquid organic extractant containing a preferred complexing agent, 3,4-dimercaptotoluene.

Abstract: In a two component extraction system for producing ammonium tungstate from aqueous alkali metal tungstate solution, the stripping solution consists essentially of water and from about 5 to about 21 percent by weight ammonium hydroxide at a pH of from about 12 to 13 wherein the stripping is carried out by dispersing the aqueous ammonia solution in the loaded organic extractant.

Abstract: In a three component extraction system for producing ammonium tungstate from aqueous alkali metal tungstate from aqueous alkali metal tungstate solution, the stripping solution consists essentially of water and from about 5 to about 21 percent ammonium hydroxide at a pH of from about 12 to about 13 wherein the stripping is carried out by dispersing the aqueous ammonia solution in the loaded organic extractant.

Abstract: A process for separating by means of an organic agent the uranium and the molybdenum contained in an aqueous liquor originating from a sulphuric attack of an urano-molybdeniferous ore which involves placing the said attacking liquor in contact with an organic extraction solution containing at least one tertiary or secondary amine in an (amine)/(Mo) molar ratio of up to 0.8, separating the molybdenum-charged organic phase from the uranium-rich aqueous phase, treating the organic phase with an aqueous liquor containing at least one mineral agent in the form of alkaline and ammonium hydroxide and/or carbonates to form an aqueous solution which is concentrated in molybdate.

Abstract: After stripping tungsten values from a loaded organic extractant in a two component extraction system for producing ammonium tungstate from aqueous alkali metal tungstate solutions, the organic extractant and aqueous solution of ammonium tungstate are fed into a settling container which includes a pair of electrodes and means for applying a direct current voltage potential for promoting coalescence of the aqueous and organic phase.

Abstract: In a two component extraction system for producing ammonium tungstate from aqueous alkali metal tungstate from aqueous alkali metal tungstate solution, the stripped organic is washed to form a wash solution which is mixed with concentrated ammonia solution to form an aqueous ammonia solution which is mixed with product ammonia tungstate and fed as the stripping solution for contacting the loaded organic extractant.

Abstract: A process for recovery of reusable chromic acid from waste chromic acid solution containing impurities, which process comprises a first step in which the solution containing chromic acid is introduced into the cathode compartment in an electro-dialysis process and free chromic acid or chromate ions in the above solution are transferred to the anode compartment, a second step in which H.sub.2 SO.sub.4 is added in at least equivalent amounts to the heavy metallic ion contained in the outlet solution, in which chromic acid ion concentration is reduced, in order to convert chemical species of the contained metallic ion and increase the H.sup.+ ion concentration and then chromate ions in the resultant solution are extracted into an organic phase with contact of an organic solvent (A), and a third step in which residual amounts of chromic acid ion remaining in the aqueous raffinate from the second step are extracted into an organic phase with contact of an organic solvent (B).