【作者】 王素敏；

【导师】 刘厚凡；

【作者基本信息】 南昌大学 ， 无机化学， 2010， 硕士

【摘要】 锌精矿和软锰矿是生产硫酸锌和硫酸锰的重要原料,世界上60%以上的硫酸锌、硫酸锰都是由锌精矿、软锰矿加工制得的。传统生产硫酸锌的工艺,其常规流程为氧化焙烧—硫酸浸出—除杂—蒸发结晶—产品。以软锰矿为原料生产硫酸锰的常规流程为：还原焙烧—硫酸浸出—除杂—蒸发结晶—产品。这两条独立生产硫酸锌、硫酸锰的方法具有流程长,投资大,能耗高,污染环境,工人劳动环境差等严重问题。因此,研究一种可行的新工艺代替传统的生产工艺,以减少污染,提高资源利用率具有重要的意义。本课题旨在利用锌精矿的强还原性和软锰矿的强氧化性,在硫酸介质中同槽浸出,经过除砷、除铁、除重金属、锌锰离子分离、蒸发结晶等工序,生产出符合饲料级标准的硫酸锌(HG 2934-2000)、硫酸锰(HG 2936-1999)产品。本课题通过大量实验数据,从理论上得出了较好的工艺条件：锌精矿、软锰矿同时浸出工艺条件：在浸出温度为90-95℃,硫酸过量系数为1.3、浸出反应时间4 h、加入催化剂硫酸亚铁的量为2 g、液固比为6-7,软锰矿的初始过量系数为1.3、反应过程中补加适当的酸和软锰矿的条件下,锌的一次浸出率达到了95.5%左右,锰的一次浸出率达到了98.9%以上,基本满足生产的要求。浸出液中砷含量也能达到饲料级产品标准,因为在浸出过程中,氧化剂软锰矿是大大过量的,它可以把原矿中的As3+氧化成AsO43-,浸出液中存在的Fe3+可以与AsO43-生成FeAsO4沉淀除去浸出液中的As。除杂工艺条件：该工艺选用P507-磺化煤油体系作为除铁萃取剂,在室温下,萃取接触时间为35min,初始料液酸度为0.45 mol·L-1H+,P507的体积分数为35%,相比O：A=1：2的条件下经四级逆流萃取,Fe3+的萃取效率达到了99%以上,Zn2+的收率为95.5%,Mn2+的收率为99.48%,可以到除铁的目的；萃Fe3+有机相用4.0 mol·L-1的盐酸,在相比O：A=2：1,反萃时间为7 min的条件下,经五级逆流反萃取,Fe3+的反萃效率可达99%以上；该萃取工艺条件应用于浸出料液同样也可以的到预期的效果。本工艺选用BaS+Zn粉的方法除重金属,在室温下加入4.0 gBaS搅拌反应1h,过滤后再加入1gZn粉,在60℃下反应4 h,Pb、Cd的含量只能报告检测不出,满足饲料级硫酸锌、硫酸锰的生产要求。锌锰分离的工艺条件：选用P507-磺化煤油体系作萃取剂,在室温下,初始pH=3.5,萃取平衡时间为10 min,相比O：A=2：3,P507的体积分数为40%的条件下,经过八级逆流萃取,锌锰离子能够达到很好的分离效果。负载有锌、锰离子的有机相,经0.02 mol·L-1的H2SO4洗涤液洗涤一次,锰离子的洗涤效率为99.77%,可以达到去除锰离子的目的,洗涤液可以返回矿粉浸出工艺,形成闭路循环。负载有锌离子的有机相,经0.7 mol·L-1的H2SO4溶液反萃,在反萃相比O：A=3：2的条件下,锌离子的单级反萃效率达到97.53%,可以满足工艺生产的要求,贫有机相可以不经处理直接返回萃取工艺而不受影响。最后硫酸锌、硫酸锰的溶液经过蒸发结晶,可以得到符合标准的饲料级硫酸锌、硫酸锰产品。本工艺具有能耗低、无二氧化硫污染、设备简单、投资费用低、易于实现自动化、产品质量高等优点。更多还原

【Abstract】 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.更多还原