全湿法处理回收银锌渣中有价金属

Study on recovering valuable metal from silver-zinc slag by wet method

对采用NaClO3 NaCl HCl体系浸出Bi等贱金属,全湿法处理银锌渣回收有价金属的工艺进行了研究.研究结果表明:当浸出温度为70～80℃,液固比为8～10,NaClO3质量为10～15g,NaCl质量为60g,浓盐酸体积为80～120mL,浸出时间为4～5h时,Bi浸出率可达99%;浸Bi液用废铁皮置换可得Bi含量达86%的粗海绵铋,将浸铋液水解可得纯度为99%的氯氧铋;浸Bi后,余渣中银含量达到70%,金含量达到1%,金和银高度富集于浸出渣中.

Feasible technology of recovering noble metal by wet method was studied from silverzinc slag. The lowpriced metal such as Bi was leached by NaClO3NaClHCl system. The leaching ratio of Bi is up to 99% when reaction temperature is 70～80℃, the ratio of liquid to solid is 810, NaClO3, NaCl and hydrochloric acid are 1015 g, 60 g, 80120 mL respectively, leaching time is 45 h. The coarse sponge bismuth, which contains above 86% Bi, is got after the leaching liquid is displased by sbeet iron. BiOCl, whose content is up to 99%, is gained when the leaching liquid is hydrolyzed. The residues containes 70% Ag and 1% Au after leaching Bi. Gold and silver are concentrated highly in leaching slag.