| zinc concentrate and pyrolusite are the important raw material of preparing zinc sulfate and manganese sulfate, and about 60% zinc sulfate and manganese sulfate were produced by zinc concentrate and pyrolusite. In the traditional production process of Zinc sulfate, its regular process for the oxidation roasting-sulfuric acid leaching-Impurity-evaporative crystallization-products. Soft manganese sulfate, pyrolusite as raw material production of the conventional process is as follows: Reduction roasting-sulfuric acid leaching-Impurity-evaporative crystallization-products.There are some serious problems of the two independent production method of zinc sulfate, manganese sulfate, such as:high investment, high energy consumption, pollution of the environment, workers and poor working environment. Therefore, the study of a possible new process to replace the traditional production process, in order to reduce pollution, improve resource utilization has an important significance.This topic is designed to use the reduction of zinc concentrate and the oxidation of manganese ore in sulfuric acid leaching in the same slot, after the removal of arsenic, in addition to iron, in addition to heavy metals, zinc-manganese ion separation, evaporation and crystallization processes to produce consistent feed-grade standard zinc sulfate (HG 2934-2000), manganese sulfate (HG 2936-1999).Through a large number of experimental data derived the best process conditions from the theory.The leaching process conditions:in the condition of the temperature 90～95℃, sulfuric acid excess coefficient of 1.3, the leaching reaction time 4 h, by adding the amount of ferrous sulfate catalyst 2 g, liquid-solid ratio of 6～7, pyrolusite excess coefficient of 1.3, during the reaction added with appropriate acid and pyrolusite, the leaching rate of zinc is amount to 95.5%, the leaching rate of manganese is amount to 98.9%, broadly in line with production requirements. Leaching solution of arsenic can achieve feed-grade product standards, because in the leaching process, the oxidant pyrolusite is greatly excessive, and it can ore in the As3+ oxidation ASO43-, the Fe3+ in the leaching solution and AsO43- can generation FeAsO4, so the As in leaching solution can be removed.Impurity removal process conditions:The process selected P507 as iron extraction agent, under the conditions of room temperature, extraction contact time of 35min, the initial acidity of 0.45 mol·L-1H+, P507 volume fraction of 35%,0:A=1:2, by the four counter-current extraction, extraction rate of Fe3+ are more than 99%, the yield of Zn2+was 95.5%, the yield of Mn2+ was 99.48%. We can go to the purpose of removing iron. And under the conditions of 4.0 mol·L-1 of hydrochloric acid,O:A=2:1,the stripping time of 7min, The five counter-current stripping, and the stripping efficiency of more than 99%;the extraction process conditions used in leaching liquid could also be of the desired effect.The process selected BaS+Zn powder to remove heavy metals. At room temperature, we add 4.0 g BaS and reaction for 1h in the stirred tank; then filtered and join 1 g Zn powder to react for 4 h at 60℃. The content of Pb2+,Cd2+ was only to report not. So it is meet the feed-grade zinc sulfate, manganese sulfate production requirements.Zn-Mn separation process conditions:selection of P507-sulfonated kerosene as extractant, in the condition of the room temperature, initial pH=3.5, extraction equilibrium time of 10min, compared with O:A=2:3,P507 volume fraction of 40%, after eight counter-current extraction, zinc-manganese ion to achieve a good separation effect.The organic phase that were loaded by zinc and manganese ions could be washed by 0.02 mol·L-1 in H2SO4 for one time, and the washing efficiency was 99.77%, and it can be achieved to the purpose of removing manganese. Then we can return the washing liquid to the slag leaching process to form a closed loop.The organic phase that were loaded by zinc can be stripped by 0.7 mol·L-1 in H2SO4, in the condition of the stripping phase O:A=3:2, the single-stage back-extraction efficiency could amount to 97.53%.And this can meet the requirements of the production process, the depleted organic phase can directly to use to the extraction process without treated.Finally, the solution of zinc sulfate and manganese sulfate through evaporation crystallization, we can absorbed feed-grade standard zinc sulfate and manganese sulfate product.The process has many benefits such as:low energy consumption, no sulfur dioxide pollution, simple equipment, invest in low-cost, easy to implement automation, product quality and high.
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