铋试金法测定高铋物料中的银

Determination of Silver in High Bismuth Slag by Bismuth Fire Assaying Method

火法试金最常用的为铅试金,当物料中铋的质量百分含量＞15％时,铅试金分析方法测定银量结果精密度差,且结果偏低.实验中研究了铋试金测定高铋铅阳极泥中银量的方法、铋试金和铅试金方法过程对比、铋试金方法中杂质元素Sb,Cu,As,Ni,Pb的干扰、铋试金过程中铋扣直接溶解滴定和铋扣灰吹二次试金方法对比.通过多家单位对精密度和加标回收率的考察,相对标准偏差（RSD）在0.33％～0.84％,加标回收率在96.38％～100.62％,方法准确、可靠.

As the most frequently used fire assaying method, the lead fire assaying method provides bad accuracy and low Ag content when it is applied to the determination of Ag in high bismuth slag （bismuth percent content 〉15%）. A method for the determination of Ag in lead anode mud with high bismuth by bismuth fire assaying was investigated. Analytical conditions were obtained through comparison of the analysis process of bismuth assaying and lead assaying method, the interference of the incidental elements such as Sb, Cu, As, Ni and Pb in the bismuth assaying method, and contrast of direct titration by dissolving bismuth button and titration with second assaying of cupellation of bismuth button. The accuracy and recovery of the method were investigated by a number of units. The relative standard deviations （RSDs） were 0.32%~0. 84% with 96.38%~100.62% recoveries.