Cyprus Metallurgical Processes Corporation

Amax Incorporated

Hazen Research, Inc.

Mark A Peters

Gustavo A Meyer

Helen S Leaver

Robert K Johnson

William G Kazel

Aqueous nickel chloride solutions containing such impurities as copper, iron, and zinc, and optionally, cobalt, and having an acid concentration ranging from about 0.2 N to 4 N HCl together with a total chloride concentration of about 4 N to 11 N are purified of said impurities by solvent extraction with an organic extractant of essentially tributyl phosphate (TBP) dissolved in a water-immiscible organic solvent, the solvent extraction being carried out at a selected concentration of TBP and a selected volume ratio of organic to the aqueous solution effective to produce a nickel raffinate substantially impoverished in said impurities.

Purification of nickel chloride solutions

A process for recovering silver from chloride solutions comprising contacting the solution with amalgams of various metals from Groups 2b, 4a, 5a, or 8b of the periodic table or copper to replace the metal with silver and recovering silver from the formed silver amalgam. The process provides an improvement in the process for recovering copper from its ores in which the copper in the ore is solubilized as cuprous copper in a leach liquor and the copper recovered from the leach liquor as cuprous chloride by crystallization, the improvement being the removal of silver from the leach liquor prior to crystallization by use of the amalgam to produce substantially silver-free cuprous chloride crystals.

Recovery of silver from cuprous chloride solutions by amalgamation

A process for recovering silver present in cuprous chloride solutions as a soluble silver chloride which comprises saturating the cuprous chloride solution with sodium chloride, subjecting the saturated solution to evaporation to co-crystallize the sodium chloride and silver chloride, separating the solid chlorides from the liquid, recovering silver from the sodium chloride-silver chloride crystals and reclaiming the sodium chloride, adding water to the liquid and cooling it to crystallize cuprous chloride. The procedure is adaptable to processes for recovering copper from its ores in which copper is reduced to cuprous chloride in a leach slurry followed by cooling the leach slurry to crystallize out the cuprous chloride from which copper is recovered by conventional techniques.

Recovery of silver from cuprous chloride solutions by co-crystallization

A method for recovering a substantially impurity-free zinc oxide product from steel-making flue dust or a similar material which comprises leaching the flue dust with concentrated ammonia and carbon dioxide to dissolve zinc and unwanted impurities, cementing the leach filtrate with zinc to remove copper, cadmium, and lead impurities, conducting a steam distillation on the cementation filtrate to precipitate basic zinc carbonate, remove the ammonia and carbon dioxide, and iron impurities, and filtering to provide a residue of essentially basic zinc carbonate, sulfur, and chromium. This residue is then washed to remove soluble sulfates, dried, and calcined at high temperatures to break down the basic zinc carbonate into zinc oxide, water washed to remove chromium and the residue of the water wash dried to produce the desired impurity-free zinc oxide product. The two water washes may be combined into one step performed after the calcining step to remove both sulfur and chromium in one wash step.

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Arvada, CO, United States of America

Mark A Peters