Abstract: Process for recovery of copper, molybdenum, gold and elemental sulfur in tailings from hydrometallurgical processing of copper sulfide ores, particularly chalcopyrite. The tailings are usually discarded, and thus the recovery of valuable elements therefrom makes the environmentally desirable hydrometallurgical processes of FIG. 1 economically feasible.The tailings are concentrated to a small bulk volume by froth flotation to reject barren gangue and the process (FIG.
Abstract: Copper is recovered from copper salts selected from the group consisting of copper chlorides, copper oxides and copper oxychlorides by reducing the finely divided solid copper salts with hydrogen under turbulent conditions at a temperature greater than the melting point of elemental copper.
Abstract: A process for the recovery of copper, molybdenum, gold and elemental sulfur in tailings from hydrometallurgical processing of copper sulfide ores, the process comprising concentrating the tailings containing elemental sulfur and copper, gold and molybdenum to a small bulk volume by froth flotation to reject barren gangue including jarosite, if present, and other impurities, separating the liquids and solids in the float concentrate, leaching the resulting residue with a solvent for sulfur followed by liquid-solids separation and recovering elemental sulfur from the liquid, leaching the residue from the sulfur solvent leach with ferric chloride to selectively dissolve copper and iron therein followed by liquid-solids separation and recovering copper from the liquid or sending it back to the hydrometallurgical circuit, leaching the residue from the ferric chloride leach with cyanide to selectively solubilize gold followed by liquid-solids separation and recovering of solubilized gold from the liquid, recovering
Abstract: 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.
Abstract: 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.
Abstract: Copper is recovered from copper salts, e.g. cuprous chloride, by means of a process comprising reducing the copper salts with hydrogen in a fluidized bed in the presence of chemically inert, generally spherical, relatively smooth, non-porous particles in order to restrain sintering of the reduced copper.
Abstract: A process is disclosed for separating cuprous chloride from a solution comprising cuprous chloride and one or more of a number of metal impurities, the process comprising crystallizing the cuprous chloride from the solution in the presence of copper as cupric chloride in a concentration of at least about 20 grams per liter.
Abstract: An improvement in conventional processes for recovering metal values from sulfide ores containing lead, zinc and silver sulfides in which process the metal sulfides are converted to chlorides by chlorination followed by solubilization of the chlorides with a sodium chloride leach and subsequent recovery of the metals from their chlorides in accordance with a conventional flow sheet including crystallization, cementation, precipitation, fused salt electrolysis, etc., with chlorine being recovered for reuse by electrolysis of the sodium chloride leach solution substantially depleted of lead, silver and zinc, the improvement being a pollution-free process which comprises:1. recycling the sodium chloride solution depleted of a major percentage of lead and silver to the sodium chloride or brine leaching step; and2.
Abstract: A pollution-free process for the recovery of high purity zinc from zinc containing material including sulfide ores which provides for maximum conservation and re-use of reagents, the process consisting of chlorinating the materials either with ferric chloride or chlorine gas followed by selective removal of metals other than zinc by standard procedures, such as, lead chloride crystallization, cementation, etc. to produce a solution containing essentially only zinc chloride and ferrous chloride. To enhance the purity of the zinc end product zinc chloride is separated from the ferrous chloride solution with a zinc selective extraction agent from which the zinc chloride is stripped with sodium chloride solution in a sodium chloride stripping circuit followed by precipitation of zinc as the carbonate.
Abstract: Copper is recovered from chalcopyrite by means of a pollution-free hydrometallurgical process which entails leaching and converting the chalcopyrite with copper sulfate in order to produce an insoluble copper sulfide, a soluble iron sulfate and sulfuric acid. A secondary leach is then conducted in order to react the copper sulfide with oxygen in the presence of a jarosite-forming cation to produce a soluble copper sulfate and an insoluble iron bearing jarosite. This copper sulfate is separated from the jarosite and sent to a copper recovery process and/or recycled. Alternatively, the copper sulfide from the initial leach may be separated from the iron sulfate solution immediately after the initial leach, and this copper sulfide can be treated with other processes to produce elemental copper and sulfur.
Abstract: A method for the separation and recovery of elemental sulfur from mixtures of foreign material and sulfur which comprises washing the foreign material and sulfur mixture to remove impurities which are deleterious to coalescence of the sulfur particles followed by adding as a cleansing and coalescence agent an alkali metal hydroxide or carbonate, heating the mixture to a temperature above the melting point of sulfur for one hour to coalesce the sulfur particles, and separating the coalesced sulfur from the foreign material.
Abstract: Accelerated reaction rates and improved yields are accomplished when sulfides of metals of groups Ib, IIb, IVa, Va and VIII of the Periodic Table are oxidized in aqueous medium to convert the sulfide sulfur to elemental sulfur by performing the reaction in the presence of activated carbon.