Abstract: The invention relates to a method for producing wood anti-rot agent of the copper-arsenic precipitate created in the solution purification of copper electrolysis, or of some other corresponding precipitate.

Abstract: An epoxidation reaction product formed by the molybdenum catalyzed reaction of propylene with tertiary butyl hydroperoxide to provide propylene oxide and tertiary butyl alcohol is separated by distillation into a propylene fraction, a propylene oxide fraction, a tertiary butyl alcohol fraction and a heavy liquid distillation fraction composed primarily of tertiary butyl hydroperoxide, tertiary butyl alcohol, dissolved molybdenum catalyst, and impurities including lower aliphatic C.sub.1 -C.sub.4 carboxylic acids, and the heavy liquid distillation fraction is saturated with ammonia to precipitate the molybdenum therefrom for recovery.

Abstract: A molten blend of an alkali metal halide containing tungsten is treated with solid particulate carbonaceous reactants, such as natural flake graphite. Tungsten monocarbide is produced having a large percentage of relatively coarse crystals. The crystal morphology is blocky or thick bladed with some equant forms and the carbon is present in the correct stoichiometric amount of 6.13% by weight, thus eliminating any need for carbon additions prior to sintering.

Abstract: An epoxidation reaction product formed by the molybdenum catalyzed reaction of propylene with tertiary butyl hydroperoxide to provide propylene oxide and tertiary butyl alcohol is separated by distillation into a propylene fraction, a propylene oxide fraction, a tertiary butyl alcohol fraction and a heavy liquid distillation fraction composed primarily of tertiary butyl hydroperoxide, tertiary butyl alcohol, dissolved molybdenum catalyst, and impurities including lower aliphatic C.sub.1 -C.sub.4 carboxylic acids, and the dissolved molybdenum content of the heavy distillation fraction is adjusted to about 300 to 500 ppm of dissolved molybdenum, if necessary, by treatment with a precipitating agent and contacted with a solid adsorbent consisting essentially of a synthetic, porous, high surface area amorphous magnesium silicate.

Abstract: Potassium impurity is removed from ammonium molybdate by dissolving the ammonium molybdate in hot acid, allowing the acid solution to cool whereby the ammonium molybdate precipitates out of the solution as molybdenum trioxide and then separating, washing and drying the molybdenum trioxide.

Abstract: The present invention is directed to tungsten halogen phosphine complex compounds having the formula W(PX.sub.3).sub.6-n L.sub.n wherein X is fluorine or chlorine, L is molecular nitrogen, acetone or other ketones or aldehydes, carbon monoxide, acetonitrile or other nitriles, diphenylethine or other ethines, diethylether or tetrahydrofurane or other open-chained or cyclic ethers, benzene or other aromatics, ethene or 1,5-cyclooctodiene or cycloheptatriene or other mono, di, or, respectively, triolefines, whereby two single-tooth ligands L can be replaced by one .mu..sup.4 -ligand or three single-tooth ligands L can be replaced by one .mu..sup.6 -ligand and n is a whole number from 0 to 5, as well as methods for the manufacture thereof. These substances are easily volatile in a vacuum and can be decomposed at extremely low temperatures and are therefore extremely well suited for CVD depositions in semiconductor technology, particularly, as via hole fillers in VLSI circuits.

Abstract: A process is disclosed to extract cobalt and optionally, at least one metal value selected from the group consisting of molybdenum, nickel, tungsten, and vanadium from metal-containing particles, such as spent hydroprocessing catalysts particles containing carbon residue. In this process, the spent catalyst particles are roasted in an oxygen-containing gas at a temperature of from 400.degree. C. to 600.degree. C., and then the roasted catalyst particles are contacted with an aqueous solution of ammonia, ammonium salt, and hydrogen peroxide. The aqueous solution has an initial pH of at least 9.5 and an initial hydrogen peroxide concentration of from 0.02 to 0.2 M. That aqueous solution is maintained at a pH of greater than 9.5.

Abstract: Disclosed is a method of reducing the turbidity of an aqueous solution of chromic acid which is formed by dissolving melted chromic anhydride in water. The chromic anhydride is contacted with water in an amount in excess of 0.02 wt %, but insufficient to form a solution, at a temperature above ambient but below about 196.degree. C. The water may be in the form of a liquid, water vapor, or steam. When the chromic anhydride is subsequently dissolved in water, the solution is much less turbid than it otherwise would be.

Abstract: Chromium oxide green in the form of donut-shaped, ring-shaped or tire-shaped particles having an internal diameter of from 0.01 to 0.5 mm and an external diameter of from 0.05 to 1.0 mm is prepared by spraying an aqueous chromium oxide green suspension through a liquid pressure nozzle into a spray dryer such that the suspension entering the drying space of the spray dryer is rotating.

Abstract: A method is disclosed for producing ammonium paratungstate from cemented tungsten carbide which comprises subjecting the cemented tungsten carbide to electrolysis by passing about 0.5 to about 20 volts through an ammoniacal solution selected from the group consisting of ammonium hydroxide-ammonium chloride solution, ammonium hydroxide-ammonium carbonate solution, and ammonium hydroxide-ammonium sulfate solution, wherein platinum and the cemented tungsten carbide serve as the anode and wherein the anode is immersed in the solution, to decompose the cemented tungsten carbide and form a solution of ammonium tungstate from which is crystallized ammonium paratungstate.

Abstract: Compositions of the formula MX.sub.2 :Y, wherein MX.sub.2 is a layer type transition metal dichalcogenide, M is a metal selected from the group consisting of niobium, tantalum, molybdenum and tungsten, X is a chalcogen selected from the group consisting of sulfur and selenium and Y is a material located between layers of MX.sub.2. The compositions may be prepared by the steps of first forming a suspension of the MX.sub.2 in a body of water. A liquid which is immiscible with water is added to the suspension. The suspension and immiscible liquid are agitated together to form a temporary emulsion. The emulsion is allowed to rest until the water and the liquid separate with an interface therebetween. A sheet-like composition of MX.sub.2 :Y forms at the interface. Preferably, the MX.sub.2 is in exfoliated, singular molecular thickness layers suspended in the water.

Abstract: Process for the fine purification of fission molybdenum, dissolved in ionic form together with ions of the fission products of I, Sn, Ce, Ru and Zr in aqueous mineral acid solution, in which the fission molybdenum is fixed by a metal oxide in a sorption step and is then released in a desorption step, comprising: (a) passing the aqueous solution over an amphoteric oxide to sorb the ions of Mo, I, Ce, Ru, Sn and Zr, (b) drying the resulting charged oxide and thereafter heating the dried oxide to a temperature of about 1200.degree. C. to about 1300.degree. C. to sublimate the Mo, and at the same time passing a carrier stream containing water vapor and oxygen over the charged oxide to take up the Mo, and (c) desublimating Mo out of the carrier gas stream by cooling to a temperature below 600.degree. C., and followed by further cooling to room temperature, dissolving the resulting Mo residue in an aqueous solution of a strong alkali to form a molybdate solution.

Abstract: According to a method and apparatus for inducing a photochemical reaction, a substrate is placed in a closed cell with a window for transmitting an ultraviolet beam therethrough and is located to oppose the window, a gas is filled to cause the phtoochemical reaction upon irradiation of the ultraviolet beam into the cell, ultraviolet pulses are repetitively controlled to emit at a predetermined intensity, an ultraviolet beam size and shape are adjusted in accordance with a size and a shape of an irradiation portion of the substrate, the repetition frequency of the ultraviolet beam is adjusted and set to effectively cause the photochemical reaction on the substrate in accordance with the adjusted ultraviolet beam size and shape, and the ultraviolet beam having the set beam size and shape at the repetition frequency is irradiated through the window of the cell.

Abstract: A method for recovering chromium from chromium-bearing material which comprises heating the material which can contain any one or combination of Co, Ni, Fe, Mo, and W with solid alkali metal hydroxide in an oxidizing atmosphere at 600.degree. C.-1000.degree. C. to form a fused material containing water soluble compounds of Cr, Mo, and W contained therein. The fused material is cooled and contacted with water to form a leach solution and a residue. The leach solution is adjusted to a pH of from about 5-8 with sulfuric acid, and a water soluble calcium salt is added. The chromium-rich liquor is then adjusted to a pH of 1-3 with sulfuric acid. Sodium metabisulfite is added to the chromium-rich liquor to reduce the chromium to the trivalent state after which the pH is adjusted to 5-8 with a base to form a precipitate of essentially all of the chromium.

Abstract: Directed to a process for producing a tungsten product of enhanced purity from ammonium paratungstate (APT) with a minimum number of processing steps which comprises mixing the APT with an ammonium solution, autoclaving the mixture at a temperature above the boiling point thereof to dissolve the APT and recrystallizing APT from the solution to yield an APT product of enhanced marketability.

Abstract: Methods are disclosed for recovering one or more of the metals of tungsten and molybdenum from metal-cellulose material. One method involves digesting the material in a mineral acid selected from the group consisting of hydrochloric acid having a concentration of at least about 4 normal, and sulfuric acid having a concentration of at least about 9 normal at a temperature of at least about 50.degree. C. for a sufficient time to form a digestion solid containing the major portion of the tungsten and a digestion solution containing a portion of any molybdenum which is present in the material, and separating the solid from the solution. Another method involves having as the starting material a metal-cellulose material comprising one or more of the metals of tungsten and molybdenum and elements selected from the group consisting of arsenic, phosphorus, silicon, and combinations thereof.

Abstract: A method is provided for treating sludge containing substantial amounts of chromium, aluminum and iron and residuals of other elements. The method comprises forming a slurry of the sludge in water at a temperature ranging from ambient to 150.degree. F. with the specific gravity of the slurry ranging from about 1.05 to 1.25, and adding a mineral acid to the slurry to provide a pH ranging from about 0.1-3 to dissolve selectively the aluminum and the chromium and leave a solids residue containing gangue material comprising an oxidized iron compound, calcium sulfate, calcium fluoride, calcium silicate among other solids. The pH of the solution is controlled at range of about 2 to 3.5 to precipitate undesirable elements, including iron, without substantially adversely affecting the dissolved chromium and aluminum.

Abstract: A process for purifying molybdenum, which comprises first leaching impure molybdenum trioxide containing potassium in a liquid medium of nitric acid, and an ammoniacal liquor, wherein the nitric acid concentration is about 3.5 to 4.0 moles per liter and the ammonium nitrate concentration is about 0.5 to 1.0 moles per liter, at greater than 50.degree. C. to solubilize the major portion of the potassium and produce a once-leached molybdenum trioxide and a first liquor, removing the once-leached molybdenum oxide from the first liquor, re-leaching the once-leached molybdenum trioxide in nitric acid having a concentration of about 3.5 to 4.0 moles per liter, at greater than 50.degree. C. to produce a twice-leached molybdenum trioxide and a second liquor, removing the twice-leached molybdenum oxide from the second liquor, water washing the twice-leached molybdenum trioxide, digesting the molybdenum trioxide in ammonium hydroxide at greater than 50.degree. C. at a pH of greater than 9.

Abstract: A process is disclosed to extract metal values selected from the group consisting of cobalt, molybdenum, nickel, tungsten, and vanadium from metal-containing particles, such as spent hydroprocessing catalyst particles containing carbon residue. In this process, the spent catalyst particles are roasted in an oxygen-containing gas at a temperature of from 400.degree. C. to 600.degree. C., and then the roasted catalyst particles are contacted with an aqueous solution of ammonia, ammonium salt, and hydrogen peroxide. That aqueous solution has an initial pH of at least 9.5 and an initial hydrogen peroxide concentration of from 0.02 to 0.2 M. That aqueous solution is maintained at a pH of greater than 9.5.

Abstract: A method of extracting tungsten values from tungsten containing ores comprising step (i) forming a mixture of a tungsten containing ore and a first mineral acid adapted to consume acid consuming substances in the ore and step (ii) thereafter adding organic anions to produce a solution containing dissolved tungsten values.

Abstract: Metal values including those of cobalt, vanadium, aluminum, molybdenum and tungsten are recovered from spent petroleum refining catalyst by acid leaching the metal values except those of molybdenum or tungsten, separating the resulting solution from the leach residue and selectively recovering the cobalt, vanadium and aluminum values from the solution and recovering the molybdenum and tungsten values from the leach residue.

Abstract: Heavy hydrocarbon containing sludges such as refinery waste streams, oil storage tank sludges and marine oil tanker ballast are treated by passing the sludges in a flow stream through an indirect dryer to vaporize liquids having a boiling point at atmospheric pressure of less than about 700.degree. F. and to provide substantially dried solid particles discharged from the dryer. The dried particles, containing heavy hydrocarbons as a coating or as a part of the solids, are conducted to a combustor/oxidizer and exposed to a high velocity flow stream of oxygen containing gas, typically low pressure forced air, to burn the residual hydrocarbons in the solids and to reduce heavy metals and the like to oxides thereof. A sludge handling system includes a rotary disk type indirect dryer connected to a lift pipe type combustor/oxidizer for thorough exposure of the dried solids to an oxygen containing atmosphere.

Abstract: In the alumino-thermit method of producing tungsten monocarbide powders, metallic iron is added to the reaction charge in quantities to control the calculated reaction temperature within the range of about 4372.degree. to about 4500.degree. F. It has been found that this process can now be controlled to produce macrocrystalline tungsten carbide powders which are very low in Ti, Ta and Nb content and have a very narrow range of total carbon contents.

Abstract: Novel single layer materials of the form MX.sub.2, where MX.sub.2 is a layer-type dichalcogenide such as MoS.sub.2, TaS.sub.2, WS.sub.2, or the like, exfoliated by intercalation of an alkali metal, and immersion in water, are disclosed. MoS.sub.2 has been exfoliated into monolayers by intercalation with lithium followed by reaction with water. X-ray diffraction analysis demonstrates that the exfoliated MoS.sub.2 in suspension is in the form of one-molecule-thick sheets. X-ray patterns from dried and re-stacked films of exfoliated MoS.sub.2 indicate that the layers are randomly stacked. By adsorbing monolayers or precipitating clusters of various species such as compounds of Co, Ni, Pb, Cd, Al, Ce, In and Zn, on MoS.sub.2 while the sulfide is suspended as single layers and then recrystallizing, a new group of inclusion compounds can be formed. In the re-crystallized or re-stacked materials, the inter-layer spacing can be expanded or contracted compared to MoS.sub.2.

Abstract: A process is disclosed for recovering tungsten, iron, and manganese from tungsten bearing material. The process involves digesting the material in a sufficient amount of sulfuric acid at a temperature of at least about 80.degree. C. for a sufficient time in the presence of coal as a reducing agent to form a digestion solution containing the major portion of the scandium, iron, and manganese and a digestion residue containing the major portion of the tungsten, followed by separating the solution from the residue. The major portion of the scandium can be extracted from the digestion solution with an organic solution consisting essentially of a mixture of tertiary alkyl primary amines which are present in an amount sufficient to extract the major portion of the scandium, and the balance an essentially aromatic solvent. The scandium is stripped from the organic with hydrochloric acid which is then separated from the stripped organic.

Abstract: This invention relates to a method of recovering non-ferrous metal sulfides from a metal ore which comprises subjecting the metal ore, in the form of an aqueous pulp, to a froth flotation process in the presence of a flotating amount of a flotation collector wherein the collector comprises a compound which corresponds to one of the formulas ##STR1## wherein R.sup.1 is alkyl, aryl or aralkyl group wherein the aryl and aralkyl can be substituted with a halo or alkyl moiety;R.sup.2 is alkyl, aryl or aralkyl group wherein the aryl or aralkyl can be substituted with a halo or alkyl moiety;R.sup.3 is aryl or aralkyl unsubstituted or substituted with a halo or alkyl moiety;R.sup.4 is alkyl, aryl or aralkyl group wherein the aryl or aralkyl can be substituted with a halo or alkyl moiety; with the proviso that at least one of R.sup.1 and R.sup.2 must be aryl or aralkyl unsubstituted or substituted;under conditions such that the metal sulfide values are recovered in the froth.

Abstract: The scarcity of high grade tungsten ores obliges users to seek to recover it from scrap materials, but drill bits in particular pose especial problems. Existing proposals to use acidic hydrogen peroxide to oxides and solubilize tungsten is extremely inefficient in reagent consumption per unit tungsten recovered.According to the present invention, hydrogen peroxide can be used considerably more efficiently in the extraction of tungsten into an aqueous acidic solution by employing certain promoters which are solid at 50.degree. C. in the form of fused blocks. These blocks release the promoter slowly into the reaction solution and achieve similar efficiency of use of hydrogen peroxide and acid but at markedly reduced consumption of promoter in comparison with the same promoter added in powder or granular form. Examples of such promoter are hydroxy or amino substituted aromatic carboxylic acids e.g. 2-hydroxybenzoic acid. The promoters can most conveniently be used in a multi-stage tungsten extraction process.

Abstract: The scarcity of high grade tungsten ores obliges users to seek to recover it from scrap materials, but drill bits in particular pose special problems. Existing proposals to use acidic hydrogen peroxide to oxidize and solubilize tungsten are extremely inefficient in reagent consumption per unit tungsten recovered.According to the present invention hydrogen peroxide can be used considerably more efficiently with sub-stoichiometric reagent addition per stage, especially from 6 to 12 stages and by the use of a small amount of certain promoters which it is believed may form a water-soluble complex with tungsten which provides an alternative route for tungsten dissolution. Many of the promoters are aromatic hydroxyl or amino acids such as 2-hydroxybenzoic acid, 2-aminobenzoic acid, 4-hydroxybenzene-phenol and its related oxidation products such as 1,4-benzoquinone. Also, certain aliphatic acids such as tartaric and epoxy succinic acid show some promotional activity.

Abstract: Heavy metals and compounds thereof and other toxic materials in industrial wastes, sludges, soils, incinerated ashes and the like are fixed and stablized in a char residue, obtained by critical region pyrolyzing techniques and appropriate proportions of cabonaceous materials intimately mixed with the sludge, to encapsulate the heavy metals with carbon bonded thereto which effectively detoxifies the residue and renders it immune to any substantial leaching out or later exposure to the toxic metals, such that the same is environmentally safe for such uses as landfill and the like.

Abstract: A process for treating a first metal, manganese-containing ore comprising contacting the manganese-containing ore with an aqueous, acidic composition and a material containing at least one metal sulfide at conditions effective to (1) chemically reduce at least a portion of the manganese, (2) solubilize at least a portion of the metal from the metal sulfide, and (3) at least partially liberate the first metal from the ore; and recovering the first metal from the ore. The use of Thiobacillus ferrooxidans and/or added ferric ion in the contacting step are also disclosed.

Abstract: Tri-alkali metal di(carboxyalkyl) dithiocarbamates and triammonium-di(carboxyalkyl) dithiocarbamates which can be characterized by the formula ##STR1## wherein R and R' can be the same or different and are selected from the group consisting of alkylene radicals, preferably alkylene radicals each preferably having from 1 to 12 carbon atoms, and wherein M is selected from the group consisting of alkali metal atoms and ammonium; their use as ore flotation depressants; and a process for making these novel compositions are disclosed.

Abstract: A process for recovering at least one first metal from a metal sulfide-containing ore comprising contacting the ore with an aqueous, acidic composition and at least one reducible manganese-containing material at conditions effective (1) to chemically reduce the manganese, (2) solubilize at least a portion of the metal from the sulfide, and (3) at least partially liberate the first metal from the ore; and recovering the first metal from the ore. The use of added ferric ion and/or Thiobacillus ferrooxidans bacteria in the above-noted contacting is also disclosed.

Abstract: A process for producing an anolyte and a catholyte for redox cells which comprises the steps of heating chromium ore together with carbonaceous substances to produce a pre-reduced chromium product produced a part of iron and chromium in chromium ore, dissolving the pre-reduced chromium product in hydrochloric acid and/or sulfuric acid iron and chromium. Thus, the dissolving step can be simplified, the predetermined concentration can be simply regulated.

Abstract: A method is disclosed for purifying molybdenum which involves reducing a molybdenum compound selected from the group consisting of molybdenum trioxide, ammonium dimolybdate, and ammonium paramolybdate to molybdenum dioxide which is then water washed to remove potassium, and produce a purified molybdenum dioxide having a potassium content of no greater than about 30 weight ppm, followed by separating the wash water from the purified molybdenum dioxide.

Abstract: Molybdenite, MoS.sub.2, is completely converted into molybdenum dioxide, MoO.sub.2, by mixing MoS.sub.2 with petroleum or coal tar pitches and heating in air at 400.degree.-600.degree. F.

Abstract: An improved process for reducing ammonium ion concentration in an ammonium ion-containing, acidic liquor is provided. The process includes the essential step of reacting ammonium ion with a persulfate.

Abstract: Metal ions are reduced from a higher to a lower oxidation stage using ferrophosphorus as the reductant.

Abstract: Metal values and alumina are recovered from spent, usually oily, catalysts by oxygen pressure leaching with sodium hydroxide and/or sodium aluminate to dissolve molybdenum, vanadium and/or tungsten and provide a solid, filterable residue containing alumina and cobalt and/or nickel, the residue is digested with sodium hydroxide to give a sodium aluminate solution and a residue enriched in nickel and/or cobalt, alumina is recovered from the sodium aluminate solution as a solid and the remaining supernatant solution is recycled to the oxygen pressure leaching step wherein the alumina content of the aluminate solution is precipitated and a bleed for metals in the aluminate solution is provided.

Abstract: A process is disclosed for recovering chromium from a chromium bearing material containing cobalt, molybdenum, and tungsten. The process involves roasting the material and alkali metal compound at a temperature of at least about 400.degree. C. for a sufficient time to react the alkali metal compound with the material and form a reacted mixture containing essentially all of the chromium, molybdenum, and tungsten as alkali salts. The reacted mixture is water leached to dissolve the alkali salts and form a leach solution containing essentially all of the chromium, molybdenum, and tungsten, and a leach solid containing essentially all of the cobalt. After separation of the leach solution from the leach solid, the pH of the leach solution is adjusted to from about 0.5 to about 3.0 with an acid and a sufficient amount of a reducing agent is added to reduce essentially all of the chromium to the trivalent state.

Abstract: Spent hydrodesulfurization catalysts containing alumina, at least one metal from the group consisting of molybdenum, tungsten and vanadium and at least one metal from the group consisting of nickel and cobalt, sulfur, and, usually, residual oil are oxygen pressure leached at a temperature of at least about 400.degree. F. with a base from the group consisting of sodium hydroxide and sodium aluminte in at least stoichimetric amount to yield a solution having a pH between about 7 and 9 containing dissolved molybdenum, vanadium and any tungsten which may be recovered and a readily filterable residue containing aluminum, nickel and cobalt which may be worked up to recover the valuable constituents, with overall processing being accomplished in an environmentally acceptable manner.

Abstract: A process for the recovery of aluminum and at least one other metal selected from the group consisting of molybdenum, nickel and cobalt from a spent hydrogenation catalyst comprising (1) adding about 1 to 3 parts H.sub.2 SO.sub.4 to each part of spent catalyst in a reaction zone of about 20.degree. to 200.degree. C. under sulfide gas pressure between about 1 and about 35 atmospheres, (2) separating the resultant Al.sub.2 (SO.sub.4).sub.3 solution from the sulfide precipitate in the mixture, (3) oxidizing the remaining sulfide precipitate as an aqueous slurry at about 20.degree. to 200.degree. C. in an oxygen-containing atmosphere at a pressure between about 1 and about 35 atmospheres, (4) separating the slurry to obtain solid molybdic acid and a sulfate liquor containing said at least one metal, and (5) recovering said at least one metal from the sulfate liquor in marketable form.

Abstract: The invention relates to a method for recovering rare metals from the combustion residues of various coals, in particular brown coals. The recovery is performed by digestion, more particularly by aqueous and/or dilute alkaline and/or dilute acidic digestion, where two or three of these steps can be combined in any desired order or they may be carried out separately. During digestion the concentration of the solution is monitored and the subsequent digestion steps are terminated at a desired concentration. The solid and liquid phase are then separated and the rare metals are isolated from the liquid phase while the solid phase, optionally after neutralization and/or washing can be utilized for example as a source of energy.

Abstract: A process is disclosed for removing potassium from relatively impure molybdenum trioxide. The process involves contacting the impure molybdenum trioxide containing greater than about 600 weight parts potassium per million with a first acid leach which consists essentially of nitric acid and ammonium nitrate at a temperature of at least about 50.degree. C. for a sufficient time and at above a 2 molar concentration of said nitric acid and an ammonium nitrate concentration of from about 1.5 to about 2 molar in said first acid leach to solubilize the major portion of the potassium and form a once leached molybdenum trioxide containing the remaining portion of the potassium which is separated from the resulting potassium containing acid leach and contacted with a second leach solution substantially similar to the first acid leach followed by separating the resulting twice leached molybdenum trioxide from the resulting potassium containing second leach.

Abstract: An improved hydrometallurgical process for the recovery of metallic copper, elemental sulfur, compounds of molybdenum and other valuable materials from copper sulfide ore concentrates, such as chalcopyrite. The process, comprising a reduction stage, metallic copper recovery stage, and a combined regeneration-purge-oxidation stage, is improved by the addition of a second reduction stage following the first or primary reduction stage, and by the addition of a by-product recovery stage after the second or secondary reduction stage. The secondary reduction stage also enhances overall process performance by allowing more flexible operating practices.

Abstract: The present invention provides a process for recovering a tungsten compound from a waste liquor containing a high-boiling organic compound and the tungsten compound, which process comprises the steps of spray-burning said waste liquor at an air ratio of 1.05 or higher under conditions of a temperature and a residence time which lie within the region of a pentagon defined by points A, B, C, D, and E in FIG. 1; quenching the combustion product by immediately bringing it into direct contact with water; and recovering the tungsten compound.

Abstract: The present invention relates to a simple process for the recovery of pure tungsten at a high yield from cemented tungsten carbide or tungsten alloys scrap. According to the invention the process consists of a series of steps characterized by certain critical parameters.

Abstract: A process is disclosed for recovering tungsten, iron, and manganese from tungsten bearing material. The process involves digesting the material in a sulfur dioxide solution at a sufficient temperature for a sufficient time to form a digestion solution containing the major portion of the scandium, iron, and manganese, and a digestion solid containing the major portion of the tungsten which is separated from the digestion solution. The major portion of the scandium is extracted from the digestion solution with an organic consisting essentially of an extracting agent which is essentially a mixture of alkyl primary amines which are present in an amount sufficient to extract the major portion of the scandium without extracting appreciable amounts of iron and manganese, and the balance an essentially aromatic solvent. After separation of the scandium containing organic from the raffinate, the organic is stripped of the scandium with hydrochloric acid which is then separated from the stripped organic.

Abstract: Disclosed is a process for beneficiating chromite ore. The process can also be used to remove SO.sub.2 from SO.sub.2 -air mixtures which would ordinarily be vented. The chromite ore is pulverized and preferably mixed with sodium sulfate. Ammonium carbonate can also be added for subsequent vaporization to increase porosity. Sulphur oxide-oxygen roasting of the chromite ore is conducted at elevated temperatures in the approximate range between 300.degree. and 1,000.degree. C. or higher at approximately atmospheric pressures. After roasting, the ore is preferably leached using an aqueous ferric sulfate solution to remove soluble undesired constituents from the roasted chromite ore. The beneficiated chromite ore shows improved chromium concentrations and chromium to iron ratios when compared to the original ore.

Abstract: A process for pretreatment at high temperature by means of an aqueous pretreatment solution, of crushed ores containing at least one usable metal element, whose gangue contains argillaceous compounds which, in the attack operation for making use of the ore, are capable of forming a stable plastic suspension in the presence of water, which makes it virtually impossible subsequently to separate the liquid and solid phases by virtue of its character being such that it cannot be subjected to filtration and/or settlement, which is characterized in that, to cause stabilization of the argillaceous gangue before the operation of subjecting the ore to attack and to produce easy separation of the liquid and solid phases after the attack operation, the ore, the granulometry of which is at most equal to the liberation sieve mesh size of the metal or metals to be put to use, and before being subjected to the attack operation for making use of the ore, is brought into contact with an aqueous pretreatment solution containin

Abstract: Tungsten monocarbide is prepared by sparging a molten composition comprising an alkali metal halide and an oxygen compound of tungsten with a gas comprising a gaseous hydrocarbon, particularly methane.