共沉淀-重量法测定高锑铋铅阳极泥中银

摘要

针对铅阳极泥中锑铋含量高及传统氯化银重量法测银时存在弊端，研究了酒石酸—PbCl2— HNO3体系沉淀银的条件和干扰情况。发现在含有酒石酸15%以上的 HNO3介质中，以 PbCl2为共沉淀剂，在70℃条件下保温30 min，能实现 AgCl 的完全沉淀，且彻底消除了铅阳极泥中 Sb、Bi 和 Cu 等元素的干扰。所建立的重量法能够快速准确测定铅阳极泥中的银，准确度可与火试金法相媲美，且方法操作简便、成本低廉，适用于高锑铋铅阳极泥中5%以上银的测定。%Aiming at the characteristics of high stibium and bismuth content in lead anode mud,to overcome the disadvantage of analysis of silver by conventional AgCl gravimetry,several precipitation conditions for AgCl in tartaric acid-PbCl2-HNO3 system were investigated in this work.The results showed that AgCl can be precipitated completely when PbCl2 was used as coprecipitator,the concentration of tartaric acid was more than 15% in nitric acid solution and temperature was 70 ℃ for 30 min.This method eliminated the interference of copper,stibium and bismuth that exist with great quantity in lead anode mud.It was a rapid and accurate method,and the results was in accord with the fire assay’s.The proposed method was simple and low cost and suitable to determine silver whose content was more than 5% and coexisted in lead anode mud with high content of stibium and bismuth.