Abstract: Lead and antimony metals are important basic raw materials and strategic materials for the development of the national defense industry, biomedicine, battery research and development, semiconductor production and other fields. At present, the Pb-Sb alloy separation process in domestic and foreign smelters has complex operation, large pollution, high energy consumption, long production process and low recovery rate. The effective development and utilization of lead and antimony resources not only has practical significance, but also has important strategic significance for promoting national economic development and scientific progress. This work introduced the gas pressurization technology, and by virtue of its technical characteristics of enhanced filtration and separation, put forward a new method of efficient and environmentally friendly separation and extraction of Pb-Sb resources. In this work, the theoretical purity and recovery rate after separation were calculated according to the phase diagram of Pb-Sb alloy using the lever principle, and the effects of different filtration temperatures, filtration pressures, filtration times, screen and melt composition on the separation results were discussed, and the separation mechanism of pressurized filtration separation was clarified. The results of SEM-EDS, metallographic microscope and XRF showed that lead migrated to the lower crucible along the pressure direction, and almost all antimony remained in the upper crucible. With the decrease of filtration temperature, the size of precipitation crystal increased, the viscosity of molten liquid phase increased, and the resistance of filter cake to liquid phase increased. The best separation conditions were obtained through experiments, under the conditions of filtration temperature T=553 K, screen N=100, filtration pressure p=0.2 MPa, and four filtration times, the upper enriched Sb phase with a content of more than 90wt%, and the lower enriched Pb phase with a content of 85wt% were successfully obtained, which was close to the theoretical value calculated from the Pb-Sb phase diagram.

Key words: Pb-Sb alloy, gas pressure filtration, Pb-Sb separation, solid-liquid separation

摘要： 目前国内外冶炼厂对Pb-Sb合金的分离工艺普遍存在操作繁杂、高污染、高能耗、生产流程长、回收率低等问题，对Pb-Sb合金进行资源化回收已经成为有色冶金行业的迫切需求。本工作介绍了气体加压技术，由于不同相之间的界面张力很小，加压过滤技术对于固液相的分离发挥了重要作用。根据Pb-Sb相图利用杠杆原理计算其理论分离效率，讨论了不同分离条件对分离结果的影响。通过SEM-EDS、金相显微镜和XRF等检测方法，证明Pb沿加压方向迁移到下部坩埚，几乎所有的Sb保留在坩埚上部。结果表明，随着过滤温度降低，析出晶体的尺寸增加，熔融液相的黏度也随之增加，滤饼对液相的阻力也增大，得到最优分离条件：过滤温度T=553 K，筛网目数N=100目，过滤压力p=0.2 MPa，过滤次数为4次的条件下，成功得到含量超过90wt%的上部富Sb相和含量为85wt%的下部富Pb相，接近于由Pb-Sb相图计算所得的理论值。

关键词: Pb-Sb合金, 加压过滤, 铅锑分离, 固液分离