Method for removing metal impurity cobalt from crude zinc raw materials to obtain zinc-containing solution

Abstract

The invention provides a method for removing a metal impurity cobalt from crude zinc raw materials to obtain a zinc-containing solution. The method comprises the steps that (1) the crude zinc raw materials are dissolved with sulfuric acid, so that a crude zinc solution is prepared; (2) a first part of zinc powder is added into the crude zinc solution to separate out sponge cadmium, and thus a crude zinc solution with cadmium primarily removed is obtained; (3) potassium carbonate and a dissolution inhibitor are added to react under the condition of pH=4.8-5.8, so that nickel hydroxide depositions are generated; then the temperature is increased, zinc powder is added again to react, cadmium is removed again, and thus, a zinc-containing solution with cadmium and nickel removed is obtained; and (4) a first part of potassium permanganate is added, part of ferrous ions in the solution are oxidized into trivalent iron ions, and manganese dioxide (MnO2) depositions are formed at the same time;then hydrogen peroxide is added to react, so that indissolvable manganic acid cobalt depositions are formed; then the temperature is increased, and a second part of potassium permanganate is added toreact till the solution is reddish or light red; then the pH value of the solution is adjusted to 5.0-5.8 with calcium carbonate powder, and the temperature is further increased till the red color disappears; and the depositions are removed through separation, and thus, the qualified zinc-containing solution with cobalt, iron and manganese removed is obtained.

Description

technical field [0001] The invention relates to a purification process of zinc liquid, in particular to a method for removing impurity metal cobalt from crude zinc raw materials to obtain a zinc-containing solution. Background technique [0002] In the existing production process of zinc sulfate, zinc carbonate, and electrolytic zinc, it is necessary to purify and remove harmful metals such as cobalt, nickel, cadmium, iron, and manganese. In the factory, there are usually processes such as the first cleaning process and the second cleaning process. The crude zinc liquid passes through these purification processes to remove impurity metals, so as to meet the product control requirements. [0003] The existing production of zinc sulfate, zinc carbonate, and electrolytic zinc for intermediate purification to remove cobalt and nickel mainly uses antimony-zinc alloy replacement and sulfuration plus arsenic purification, which needs to be able to achieve the purpose of purificatio...

AI Technical Summary

Problems solved by technology

[0004] 1. Alloy zinc powder is used to replace cobalt and nickel, which is costly

Because the alloy zinc powder is double-layered with the same ion, one is that the amount of expensive alloy zinc powder added is three times the number of moles, so the amount added is large; time consumption;

[0005] 2. There is a sudden safety hazard to the operator

And when it is used for electrolytic zinc solution, nickel and cobalt are difficult to remove, causing the color of zinc carbonate products to turn green and black, which affects the quality of downstream products. When it is used as electrolytic zinc, it is easy to cause The current plate is short-circuited, the plate is burned, and the loss is large

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