Method for cleaning copper electrolyte and removing impurity from it

Abstract

The copper electrolyte purification method for removing antiomony and bismuth is characterized by that in the copper electrolyte a high-arsenic solution is added to make the As-contained concentration of said electrolyte retain at 10g / L-15g / L, so that most impurities of Sb and Bi in the copper electrolyte can be combined with As to form supersaturated antimony arsenate and bismuth arsenate crystal substances, these crystal substances can be come into anode mud, and can be removed. Said invention possesses obvious effect for removing Sb and Bi, and its removed rate can be up to 100%, and its cost is low.

Description

(1) Technical field [0001] The invention relates to a method for purifying and removing impurities of a copper electrolyte, relating to a method for purifying and removing impurities of an electrolyte in a nonferrous metal hydrometallurgy process, in particular to a method for purifying and removing antimony and bismuth from a copper electrolyte. (2) Background technology [0002] During the electrolytic refining of crude copper soluble anode, since the oxidation-reduction potential of Sb and Bi is close to that of Cu, when these impurities accumulate in the electrolyte to a certain concentration, they may be reduced and precipitated on the cathode together with copper, reducing the cathode copper. quality. In addition, Sb and Bi are easy to form floating anode slime with As. The higher the concentration of Sb and Bi in the electrolyte, the greater the possibility of forming floating anode slime, which will pollute the electrolyte and reduce the quality of cathode copper. T...

AI Technical Summary

Problems solved by technology

This process has the following three major defects: First, in order to meet the requirements of removing Sb and Bi, the amount of net liquid required by the conventional electrowinning method is relatively large, resulting in an imbalance of copper and acid in the electrolyte. In order to maintain the copper acid in the electrolyte balance, and it is necessary to build a copper sulfate production system to re-dissolve all the crude copper sulfate produced and return it to the electrolysis system

The second is that due to the large amount of net liquid required for conventional electrowinning, excessive arsenic removal of the electrolyte results in a severely low arsenic concentration in the electrolyte. In addition, the ratio of As to Sb+Bi in the anode copper is low, making the anode The dissolution rate of Sb and Bi in copper in electrolyte is very high

Third, the comprehensive removal rate of impurities in this process is low

Due to the above three major defects, in order to keep the balance of antimony, bismuth, copper and acid in the electrolyte at the same time, it is necessary to continuously expand the net liquid capacity and increase the net liquid volume, resulting in an excessively long electrolyte purification process.

The system is huge. Although it can suppress the growth of antimony and bismuth in the electrolyte, it is bound to increase the infrastructure investment continuously, and the cost of removing impurities will also increase significantly, so that the production cost of cathode copper will continue to rise.