Method for purifying copper electrolyte by using chemical reduction method

Abstract

The invention provides a method for purifying a copper electrolyte by using a chemical reduction method. The method comprises the following steps of adding reducing agents comprising hydrazine hydrate, sulfur dioxide and the like, and a compound which contains Cl-irons, Br-irons and I-irons and is used as additives in the copper electrolyte, filtering after the reduction reaction, or evaporating and crystallizing copper sulfate and filtering to obtain the purified electrolyte, and adding the purified electrolyte in an electrolytic bath to return to an electrolyzing system. Adopting the chemical reduction method to purify the electrolyte, the invention eliminates black copper powder and arsenide hydrogen generated in an electro-deposition method and greatly reduces the energy consumption during purifying the copper electrolyte.

Description

Technical field: [0001] The invention relates to a method for purifying copper electrolyte, which is to add a suitable reducing agent into the copper electrolyte, mainly to make As(V) in the copper electrolyte be reduced and co-precipitate with impurity elements Sb and Bi in the electrolyte Purify the copper electrolyte. Background technique: [0002] In the electrolytic refining of copper, the anode efficiency is higher than the cathode efficiency, and Cu 2+ As the concentration increases, so does the impurity concentration. In order to ensure the quality of cathode copper and maintain normal production, the copper electrolyte must be purified. Purification purpose of copper electrolyte (1) Copper removal, generally with CuSO 4 ·5H 2 O or standard cathode copper is removed; (2) In addition to As, Sb, Bi, many methods are used, and electrowinning is widely used; (3) Ni is recovered, usually by concentrated evaporation to remove Cu and remove As, and nickel sulfate is rec...

AI Technical Summary

Problems solved by technology

The technology of electrowinning to purify copper electrolyte is mature, and the effect of removing Cu and As, Sb and Bi is good, but the obvious disadvantages are ① use of insoluble anode, high cell voltage, and high energy consumption; ② highly toxic arsine is precipitated; ③ contains arsenic , antimony, and bismuth black copper needs to be returned to smelting, resulting in the circulation and accumulation of arsenic, antimony, and bismuth impurities

Its disadvantage is that the resin exchange capacity is limited, and the Cl produced by the analysis - Contamination of electrolyte and other issues

The disadvantages of the extraction method are strong extraction of As, weak extraction of antimony and bismuth, large loss of extraction agent, high cost, etc.

The precipitation effect of the precipitation method is not ideal, the amount of precipitant is large, and the operation is complicated

The patented technology of copper arsenite to purify copper electrolyte still exists (1) the preparation of copper arsenite generally uses the highly toxic chemical arsenic as raw material, which requires strict management; (2) As the electrolysis proceeds, As in the electrolyte accumulates , still needs arsenic removal

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