Disclosed is a method for preparing vanadium or vanadium alloy powder from a vanadium-containing raw material through a shortened process, including: calcinating a mixture of a vanadium-containing raw material and an alkali compound for oxidation to form a water-soluble vanadate; purifying the vanadate followed by vanadium precipitation to produce an intermediate CaV.sub.2O.sub.6 with high purity; dissolving CaV.sub.2O.sub.6 in a molten-salt medium together with other raw materials to form a uniform reaction system; and introducing a reducing agent to the system followed by separation, washing and drying to produce vanadium or vanadium alloy powder having a particle size of 50-800 nm and a purity of 99.0 wt % or more. The method can continuously process vanadium-containing raw materials to prepare vanadium or vanadium alloy powder.

Disclosed is a method for preparing vanadium or vanadium alloy powder from a vanadium-containing raw material through a shortened process, including: calcinating a mixture of a vanadium-containing raw material and an alkali compound for oxidation to form a water-soluble vanadate; purifying the vanadate followed by vanadium precipitation to produce an intermediate CaV.sub.2O.sub.6 with high purity; dissolving CaV.sub.2O.sub.6 in a molten-salt medium together with other raw materials to form a uniform reaction system; and introducing a reducing agent to the system followed by separation, washing and drying to produce vanadium or vanadium alloy powder having a particle size of 50-800 nm and a purity of 99.0 wt % or more. The method can continuously process vanadium-containing raw materials to prepare vanadium or vanadium alloy powder.

A process for treating spent catalyst containing heavy metals, e.g., Group VIB metals and Group VIII metals is provided. In one embodiment after deoiling, the spent catalyst is treated with an ammonia leach solution under conditions sufficient to dissolve the group VIB metal and the Group VIII metal into the leaching solution, forming a leach slurry. After solid-liquid separation to recover a leach solution, chemical precipitation and solids repulping is carried out to obtain an effluent stream containing ammonium sulfate (Amsul), ammonium sulfamate, Group VB, Group VIB and Group VIII metals. Following sulfidation, the Group VIII metal is fully removed and Group VB and Group VI metals are partially removed from the Amsul stream. In the additional steps of oxydrolysis and iron precipitation, an effective amount of ferric ion at a pre-select pH is added to form insoluble complexes with the Group VB and Group VIB metals, which upon liquid-solid separation produces an effluent ammonium sulfate stream containing less than 10 ppm each of the Group VB and Group VIB metals.

A plant for recovering metals and/or metal oxides from industrial process waste, in particular oil product refining waste, comprises a furnace; a feed line connected to a main inlet of the furnace and configured to feed the furnace with a solid waste containing metals, in particular in oxide form; an outlet line, connected to a solid phase outlet of the furnace and configured to draw a metal-enriched solid phase out of the furnace; the furnace is a belt conveyor furnace having a belt conveyor closed in a loop with a substantially horizontal configuration and having a top face, which receives the waste to treat and conveys it between two longitudinal opposite ends of the belt conveyor furnace respectively provided with the main inlet and the solid phase outlet.

A plant for recovering metals and/or metal oxides from industrial process waste, in particular oil product refining waste, comprises a furnace; a feed line connected to a main inlet of the furnace and configured to feed the furnace with a solid waste containing metals, in particular in oxide form; an outlet line, connected to a solid phase outlet of the furnace and configured to draw a metal-enriched solid phase out of the furnace; the furnace is a belt conveyor furnace having a belt conveyor closed in a loop with a substantially horizontal configuration and having a top face, which receives the waste to treat and conveys it between two longitudinal opposite ends of the belt conveyor furnace respectively provided with the main inlet and the solid phase outlet.

There is a process for the selective recovery of transition metals from an organic stream containing transition metals. The organic stream and possibly a first extractor if solid, are melted up to the liquid state. The extractor consists of an ionic liquid or a mixture of two or more ionic liquids and the ionic liquid contains an ammonium salt as cation and as anion an anion with chelating properties. A melted organic stream and a first extractor, optionally melted, are fed to a first liquid-liquid extraction unit working at a temperature of at least 150° C. where the liquid-liquid extraction is carried out obtaining a liquid mixture containing an ionic liquid, or a mixture of two or more ionic liquids, and metals. After extraction, the liquid mixture is cooled at a temperature between 0° C. and 70° C. and becomes biphasic; then the cooled mixture is sent to a first separation unit, to separate a liquid phase that contains ionic liquids and metals, and a metal-depleted solid phase. After the first separation, the separated metal-depleted solid phase is optionally sent to a washing unit to which a solvent is fed, so as to eliminate the residual ionic liquid by transferring it into the solvent and obtaining a metal-depleted solid phase. Then the separate liquid phase containing ionic liquids and metals is sent into a liquid-liquid precipitation and separation unit, adding a counter-solvent, thereby obtaining a solid phase containing the metals and a liquid stream containing counter-solvent and ionic liquids.

The present disclosure broadly relates to a process for recovering scandium and/or vanadium values from various feedstocks. More specifically, but not exclusively, the present disclosure relates to a process for the selective recovery of scandium and/or vanadium values from a feedstock, the process comprising: leaching the feedstock in a sulfuric acid solution while simultaneously sonicating the sulfuric acid solution thereby producing a pregnant solution; and selectively removing scandium and vanadium compounds from the pregnant solution using a solvent extraction process.

The present disclosure broadly relates to a process for recovering scandium and/or vanadium values from various feedstocks. More specifically, but not exclusively, the present disclosure relates to a process for the selective recovery of scandium and/or vanadium values from a feedstock, the process comprising: leaching the feedstock in a sulfuric acid solution while simultaneously sonicating the sulfuric acid solution thereby producing a pregnant solution; and selectively removing scandium and vanadium compounds from the pregnant solution using a solvent extraction process.

The present application relates to the technical field of non-ferrous metal reduction, and specifically to a method and device for accurately controlling a reduction valence state of high-purity vanadium pentoxide. An example method includes: introducing a reducing gas into the vanadium pentoxide to carry out a reduction reaction under a heating condition to obtain a mixture; weighing the mixture during the reduction reaction, and stopping the reaction when the weight of the mixture reaches a specified value; and introducing a cooling gas into the mixture for cooling to obtain calcine. An example device includes: a conveying member; a casing arranged on the conveying member; a partition member on the casing and dividing the inside of the casing into a reduction zone and a protection cooling zone; a material storage member on the conveying member for placing materials; and a weighing member on the conveying member.

The present application relates to the technical field of non-ferrous metal reduction, and specifically to a method and device for accurately controlling a reduction valence state of high-purity vanadium pentoxide. An example method includes: introducing a reducing gas into the vanadium pentoxide to carry out a reduction reaction under a heating condition to obtain a mixture; weighing the mixture during the reduction reaction, and stopping the reaction when the weight of the mixture reaches a specified value; and introducing a cooling gas into the mixture for cooling to obtain calcine. An example device includes: a conveying member; a casing arranged on the conveying member; a partition member on the casing and dividing the inside of the casing into a reduction zone and a protection cooling zone; a material storage member on the conveying member for placing materials; and a weighing member on the conveying member.