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Zinc sulphate solution purification process is an important step in the production of zinc hydrometallurgy the net liquid directly affect the quality of the zinc electrowinning current efficiency and the electrical mass of zinc, nickel, cobalt is the most difficult to remove impurities in the zinc sulphate solution. The actual production of the domestic industry in addition to the application of more nickel and cobalt replacement method and xanthate law, foreign countries also have factory beta-naphthol to cobalt removal, but this method is still in the stage of laboratory research, and no industrial applications reported. The replacement method requires adding an excess of zinc powder, to maintain a high replacement temperature, usually also added in order to reduce the consumption of zinc powder, the arsenic salt or salts of antimony do activator, improve the quality of net fluid; This law will need to consume a large amount of zinc powder, not economic, and the work environment was quite poor, the output purification slag is not easy to deal with. For the status quo, access to a large heavy metal collector and water solution on the basis of data in addition to nickel, cobalt method, the selection of a new type of modified curing agent RnYm instead of xanthate purification to remove nickel, drill new method. The first study conducted in the removal of nickel, cobalt, pure water system under test; then the removal of nickel, cobalt test system of pure zinc sulfate; zinc sulfate solution last hydrometallurgy outputs actual removal of nickel, The cobalt Test. In the course of the study, from a theoretical point of view vulcanization settlement nickel, cobalt reaction carried out a full analysis of the pilot study aspects of reagent, reaction temperature, reaction time, the pH of the system value on this basis, and this reagent to determine these parameters in addition to nickel, cobalt, and the inherent law. The test results show that in the pure water system, when the reagent with an aqueous solution of nickel, the ratio of the amount of metal drill reaches about 19:1,10:1, nickel, cobalt removal rate reached 99.44%, 97.93% , nickel, cobalt and the residual concentration of the purified solution were also dropped 0.1231mg / L and 0.5133mg / L (Zinc electrically requirements ≤ 1mg / L), also found that: compared to the removal of nickel and cobalt removal, effective the pH value range is relatively wide, the faster the reaction, the reaction temperature is lower; occurs when the type of result in the pure zinc sulfate system, the removal of impurities of nickel and cobalt, nickel removal rate is substantially independent of an aqueous solution of high concentration (100 g / L), the influence of zinc ions and cobalt in its removal rate of only 10% or less, far less than purification requirements. For this purpose, the interference of the zinc ion concentration gradient verification test, when the zinc ion concentration in the aqueous solution of less than 800mg / L, cobalt sedimentation little interference. For this situation, added Fe3 test results show that when the appropriate amount of Fe3 can greatly improve the settling efficiency of the cobalt, the the residual cobalt concentration after purification liquid is fully able to meet the requirements of the zinc electrowinning, but at the same time, a vulcanizing agent consumption will subsequently increase, is not conducive to control production costs. The final validation test of the hydrometallurgy outputs the actual solution purification cobalt. The xanthate method This method is in use today and zinc powder - the antimony salt method compared respectively with a purifying effect, especially to deep purification of nickel, reagents absolute consumption and low cost production.
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