Abstract: A process is described for the removal of chloride impurity from zinc sulphate solution. The process comprises the steps of forming a slurry of said solution with an inert particulate support material having elemental silver dispersed thereon, and an oxidizing agent, agitating said slurry at a temperature between about 60.degree. and about 100.degree. C. for precipitation of silver chloride on said support material, filtering said slurry to separate purified zinc sulphate solution from the support material containing the precipitated silver chloride, and treating said separated support material containing precipitated silver chloride with a reductant in an aqueous alkaline medium to regenerate elemental silver on said support material.

Abstract: Embodiments of a method are disclosed for producing large size cadmium mercury telluride (CMT) sputtering targets of a homogeneous composition. Sputtering targets of CMT having a general formula Cd.sub.x Hg.sub.1-x Te wherein x has values in the range of about 0.14 to 0.60 are prepared by compacting finely divided CMT of a particle size smaller than 150.mu. in a die into a coherent compact having a density of at least 97% theoretical density. CMT with an x value of about 0.14 to about 0.20 preferably is compacted at a die preheat temperature of about 100 to 300.degree. C. and at a compacting pressure of at least about 400 MPa. CMT having an x value of about 0.20 to about 0.60 preferably is compacted at a die preheat temperature of about 300.degree. C. and a compacting pressure of about 160 to 275 MPa. The die may be evacuated to a pressure of less than about 133 Pa absolute prior to compacting.

Abstract: The process of the invention is for the separate recovery of elemental sulfur and residual sulfides and metal salt solution from reaction slurries obtained from leaching of metal sulfides in ores and concentrates.

Abstract: Gallium and other values are recovered from phosphorus-furnace flue-dust by treating dust with sulfuric acid to form a solution and a residue. The residue may be treated for recovery of values. Zinc is precipitated from the solution as zinc ammonium sulfate hexahydrate and an alkaline material is added to precipitate a gallium concentrate and to form a gallium-free solution, which may be treated for recovery of sulfate and phosphate values. The gallium concentrate may be upgraded by mixing concentrate with lime to precipitate calcium phosphate and by subsequently adding sodium hydroxide to redissolve coprecipitated gallium and aluminum compounds. Residual precipitate is recycled and the solution is neutralized to precipitate an upgraded concentrate. Aluminum may be removed as calcium aluminate. Upgraded concentrate may be dissolved in alkaline solution and the solution electrolyzed for deposition and recovery of gallium.

Abstract: A process for producing gallium by electro-deposition from an acidic gallium chloride solution wherein electrolysis is conducted in the presence of metal ions of at least one metal from the group consisting of aluminium, zinc, calcium, magnesium, sodium and potassium dissolved in said solution.