Determination of gold and silver in copper telluride by sulfuric acid separation-fire assay gravimetric method
LI Xianhe, WAN Shuang
(Shandong Yanggu Xiangguang Copper Co., Ltd., Liaocheng 252327, China)
而得到试样中的碲含量。实验结果表明，浓硫酸的加入量为30 mL，残余量应不少于15 mL。火试金中硅酸度为1 左
Abstract：A method was established to determine gold and silver in copper telluride by sulfuric acid separation-fire
assay gravimetry. Copper telluride sample was dissolved with sulfuric acid, after being filted, copper and tellurium was
removed to get the precipitate, which was ashed, mixed, and melted at high temperature to obtain lead button. Ash was
removed from the lead button by blowing to obtain gold and silver particles which were divided into gold by nitric acid,
and the gold content was determined by gravimetric method. The mass of the gold particles and the amount of impurities
in the gold separating liquid and washing liquid were reduced by using the mass of the composite particles to obtain the
silver amount. The method of ash pan and residue melting method were adopted to correct the detection results, or tellurium
and copper-containing materials were used as the matrix together with pure gold and pure silver, which was determined
by the same method as the sample, and the detection result was corrected according to the recovery rate of gold and silver.
The experimental results showed that the proper addition amount of concentrated sulfuric acid was 30 mL, and the residual
amount should be not less than 15 mL. The silicic acid degree in fire test gold was about 1, and the appropriate temperature
for the sample to enter the furnace was 900℃. The relative standard deviation of gold and silver was 0.33%-1.97% and
0.28%-1.27% (n=9), respectively. The recovery rate of gold was 98.5%-100.2%, and that of silver was 95.5%-101.4%. The
method fully meets the requirements of production control and trade settlement.
Keywords：sulfuric acid separation; fire assay gold gravimetry; copper telluride; gold; silver
李先和，万双. 硫酸分离- 火试金重量法测定碲化铜中的金和银[J]. 化学分析计量，2020，29(1)：13-17.LI X H，WAN S. Determination of gold and silver in copper telluride by sulfuric acid separation-fire assay gravimetric method[J]. Chemical analysis and meterage，2020，29(1)：13-17.