Method for extracting nickel, cobalt and copper from nickel-copper alloy chloride leaching solution

Abstract

The invention relates to the field of wet metallurgy and chemical industry and particularly discloses a method for extracting nickel, cobalt and copper from a nickel-copper alloy chloride leaching solution. The method includes the steps that (1) the chloride leaching solution is heated, the pH value of the solution is adjusted by slowly adding liquid ammonia under the stirring condition, and the solution is filtered so as to obtain a filtrate; (2) the saponification rate is controlled through a 2-ethylhexyl phosphate mono-2-ethylhexyl ester and a sulfonated kerosene extraction agent, and cobalt and copper ions in the filtrate in the step (1) are extracted; (3) cobalt in a loaded organic phase in the step (2) is washed with diluted hydrochloric acid, and copper in the organic phase obtainedafter cobalt washing is finished is back-extracted through diluted sulphuric acid; (4) an ammonium hydrogen carbonate solution is reacted with an extraction raffinate in the step (2), the reaction endpoint is controlled, and nickel powder is obtained through reduction; (5) the ammonium hydrogen carbonate solution is reacted with a cobalt chloride washing solution in the step (3), the reaction endpoint is controlled, and cobalt powder is obtained through reduction; and (6) the copper sulfate back extraction solution in the step (3) is evaporated and crystallized, and then copper sulfate pentahydrate is obtained.

Description

technical field [0001] The invention relates to the fields of hydrometallurgy and chemical industry, in particular to a method for extracting nickel, cobalt and copper from nickel-copper alloy chlorinated leachate. Background technique [0002] The nickel-copper alloy produced during the pyro-smelting process of nickel sulfide ore contains valuable metals such as nickel, cobalt and copper, in addition to a small amount of elements such as iron, arsenic and lead. Nickel-cobalt-copper is the three most valuable metals among non-ferrous metals. The current main treatment process for this type of alloy is to leaching the alloy with hydrochloric acid and chlorine gas. The leaching solution is first extracted with copper-specific extractant, and then back-extracted with sulfuric acid to obtain a high-acid copper sulfate solution for the production of electrolytic copper. The raffinate after extracting copper is removed with P204, cobalt is extracted with C272, and back-extracted ...

AI Technical Summary

Problems solved by technology

[0003] In order to solve the problems in the prior art that the leaching effect of the alloy is good, but the liquid treatment process after leaching is long, the metal recovery rate is low, the production cost of using ammonium oxalate as the precipitant is high, and the amount of wastewater is large and difficult to handle. Method for extracting nickel, cobalt and copper in nickel-copper alloy chloride leaching solution