低温碱性一步熔炼处理分银渣

Process of silver separated residue by low temperature alkaline one-step smelting

采用低温碱性一步熔炼处理分银渣生产贵铅合金,产出的碱浮渣再经水浸获得含锡、锑、砷溶液。考察了碱渣比、盐渣比、碳粉加入量、熔炼温度、熔炼时间对锡、锑、砷浸出率以及铅、铋回收率的影响。结果表明:熔炼过程的优化条件为:碱渣比0.6,盐渣比0.4,熔炼温度600℃,熔炼时间6 h,碳粉加入量为20%。在此优化条件下,锡、锑、砷浸出率分别为85.95%、93.06%和98.62%,铅、铋被还原为单质捕集贵金属形成贵铅合金,回收率分别为93.17%和99.99%。本工艺流程短、试剂耗量少,实现了分银渣中有价金属的高效初步分离富集。

Processing of silver separated residue（SSR） by low temperature alkaline one-step smelting was adopted to produce precious lead alloy and obtained a solution of Sn, Sb, As followed by water leaching of alkaline slag. The effects of the mass ratio of alkali to SSR, the mass ratio of salt to SSR, smelting temperature, smelting time and addition of coke powder were determined on the leaching efficiencies of As, Sn and Sb, and the recovery rates of Pb and Bi. The results show that the optimum conditions of the process are determined as follows： the mass ratio of alkali to SSR is 0.6, the mass ratio of salt to SSR is 0.4, the smelting temperature is 600 ℃, the smelting time is 6 h and the content of coke powder is 20%. Under the optimum conditions, the leaching efficiencies of As, Sn and Sb reach 98.62%, 85.95% and 93.06%, respectively, while Pb and Bi are reduced to form precious lead alloy and the recovery rates of Pb and Bi reach 93.17% and 99.99%, respectively.This process provides a simple, highly effective way to seperate and extract precious metals.