基于低温还原相转化的硫化锑矿清洁提取基础研究

Developing an clean and efficient method of antimony metallurgy is important for antimony smelting industry who needed technology upgrading urgently. Zinc has a greater affinity with sulfur than antimony in reducing atmosphere, as a consequence, we proposed a new metallurgy-beneficiation united method based on reducing phase transformations to extraction Sb from stibinite at low-temperature. We adopt high fluorine and chlorine-bearing secondary ZnO ash, which is refractory resources, as phase transformation agent for Sb2S3 phase transformation, and reaction products Sb and ZnS were separated by dressing methods. The new method is of simple operation, low-temperature and cleaning process and comprehensive utilization, while it needs to be supported with theoretical study of the phase transformation.. Based on this, we intend to scientific study the basic theory and the key regulated technology of reducing phase transformation process between Sb2S3 and ZnO. Basic on thermodynamic analysis, we intent to research phase equilibrium and reaction mechanism of phase transformation process, and then, we set up the basic physical- chemistry theory. Farther, reaction kinetics and reaction behaviors of the associated metals and gangue were investigated, and the controlled step and distribution law were checked out to provide a guidance for process regulation. Last, the regulatory mechanisms, involving the condition optimizing of new process, the status and physical property of the phase transformation products, was researched at the same time. Base on above study, we set up the comprehensive regulatory mechanisms of phase transformation process. Finally, the basic theory of clean extraction of stibnite based on phase transformation will be established, providing a new thread for cleaning extraction of heavy-metals sulfide materials.

开发新的清洁高效炼锑方法对于急需进行技术升级的锑冶炼行业具有重要意义。利用锌比锑亲硫性强的特点，本项目提出了基于低温还原相转化的硫化锑矿冶-选提取新方法，以含氟氯高的次氧化锌对硫化锑进行相转化，经还原固硫反应生成金属锑和硫化锌，再选矿分离得到锑粉和硫化锌精矿，新方法具有操作简单、低温清洁和资源综合处置利用的特点，但当前亟须相转化过程基础理论的支撑。. 基于此，项目拟从还原相转化的基础理论和转化过程调控机制两个方面进行研究。在热力学分析的基础上，重点研究转化过程相平衡和转化机理，以建立相转化过程物理化学理论。进而通过对相转化动力学和伴生物反应行为的研究，查清限制步骤和元素分配规律，为过程调控提供指导。最后进行相转化的工艺条件优化和转化产物性状的调控，建立硫化锑还原相转化过程综合调控机制。最终形成系统的硫化锑矿低温还原相转化清洁提取的基础理论，并为同类硫化物料的处置提供新的技术思路。

开发新的清洁高效炼锑方法对于急需进行技术升级的锑冶炼行业具有重要意义，利用锌比锑亲硫性强的冶金性质和次氧化锌相对低廉的经济特性，提出了基于低温还原相转化的硫化锑矿冶-选提取新方法。主要研究了Sb2S3-ZnO-C体系热力学和相平衡、转化历程、相转化反应动力学、工艺条件优化和产物性状调控、元素行为和全流程工艺集成等内容，主要结果如下：.(1)热力学分析表明Sb2S3可以直接一步生成金属Sb，且稳定区间易控制，合适的焙烧温度为300-800℃；.(2)Sb2S3-ZnO-C三元体系在800℃时充分转化为Sb和ZnS，硫化锑还原固硫焙烧的最佳条件为：焙烧温度为800℃、碳粉粒度为100 ~ 150目、ZnO 1倍理论量、焙烧时间为2 h，锑生成率和固硫率分别达90.40%和94.8%。.(3)硫化锑相转化的反应历程为先在低温500-700℃下发生固硫反应生成Sb2O3和ZnS，Sb2O3在800℃温度下还原成金属锑，这为硫化矿脱硫焙烧提供了新的思路，有望取代高温氧化焙烧脱硫。.(4)分别获得了Sb2S3-ZnO和Sb2S3-ZnO-C两个体系的反应活化能和动力学方程等关键数据，理论指导最在限度转化反应进行。.(5)证实高温有利于金属锑颗粒长大，而缓冷则有利于获得晶型完整、独立赋存的产物颗粒，为焙烧颗粒的定向调控提供了手段。.(6)提出并验证了硫化锑金矿还原固硫焙烧-重浮选别分离的完整工艺，以硫化锑精矿为原料，获得了Sb粉品位92.06%，锑直收率90.57%、金回收率87.82%，浮选ZnS精矿品位79.10%、锌直收率89.23%的关键工艺指标，证实了工艺可行性，具有操作易控、设备投资低、清洁无硫的特性。. 研究结果学术价值和科学意义均大，有望提供清洁、低碳的锑冶炼新工艺，并为同类重金属硫化物料清洁处置提供借鉴。.