含铋高锑冶炼渣浸出液梯级分离回收砷、锑、铋

针对传统锑、铋分离过程中,砷、锑、铋分离不彻底,有价元素回收率不够高等问题,采用还原沉砷、水解沉锑、中和除氯、中和沉铋等方法对含铋高锑冶炼浸出液进行处理,对温度,反应时间等影响条件进行了考察。结果表明,在最佳条件下,通过加入次亚磷酸钠将砷酸根还原为砷单质,最后砷以氧化砷的形式被回收,回收率达到了91.99%;沉砷后液加水进行水解沉淀,锑以SbOCl的形式沉淀下来,沉淀率在95%左右;将SbOCl加入氨水中进行除氯,锑以氧化锑的形式沉淀分离,除氯率达到了96%;沉锑后液加入一定量的氨水来中和,铋以BiOCl沉淀的形式分离出去,沉淀率达到99%左右,实现了砷与锑、铋的梯级分离与回收。

Cascade separation and recovery of arsenic, antimony and bismuth from high antimony smelting slag containing bismuth

In order to solve the problems of incomplete separation of arsenic, antimony and bismuth and low recovery rate of valuable elements in the traditional separation process of antimony and bismuth, the leaching solution of high antimony containing bismuth was treated by reducing precipitation of arsenic, hydrolytic precipitation of antimony, neutralization dechlorination and neutralization of bismuth. The temperature and reaction time were investigated and analyzed. The results show that arsenate can be reduced to arsenic element by adding sodium hypophosphite under the optimum conditions. Finally, arsenic was recovered in the form of arsenic oxide, and the recovery rate reached 91.99%. After arsenic precipitation, water was added to the solution for hydrolytic precipitation, and antimony was precipitated in the form of SbOCl, and the precipitation rate was about 95%. SbOCl is added to ammonia for chlorine removal operation, antimony is precipitated and separated in the form of antimony oxide, and the chlorine removal rate reaches 96%; after antimony precipitation, a certain amount of ammonia water is added to neutralize bismuth, bismuth is separated in the form of BiOCl precipitation, and the precipitation rate of bismuth is controlled at about 99%, thus realizing the cascade separation and recovery of arsenic, antimony and bismuth.