Determination of gold, silver, platinum and palladium in gold residue by fire assay gravimetric method combined with inductively coupled plasma atomic emission spectrometry
LIU Fangmei
Fujian Key Laboratory for Green Production of Copper and Comprehensive Utilization of Associated Resources Zijin Copper Co., Ltd., Shanghang 364204,China
Abstract：The accurate determination of the contents of gold, silver, platinum, and palladium in gold residue was an important technical support for the recovery of silver by semi-wet treatment process of copper anode slime. The traditional determination methods of gold and silver (fire assay gravimetric method) in rare and precious metal materials such as crude gold or crude silver usually had some disadvantages, including long process, one-by-one determination, presence of interfering elements including platinum and palladium. It was lack of corresponding standard analysis methods for platinum. Thus, the actual detection requirements were hardly met. The sample was treated by fire assay wrap lead cupellation method to obtain the granule containing platinum and palladium. After granule was weighted, the granule was divided for replenishing silver cupellation. After the separation of gold with treatment of nitric acid, the gold particle and its corresponding solution were obtained. The gold particle was weighted and dissloved, and the contents of platinum and palladium in gold particle and its corresponding solution were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Moreover, the contents of gold and silver were replenished and corrected. Consequently, a method for determination of gold, silver, platinum, and palladium in gold residue was established by fire assay gravimetric method combined with inductively coupled plasma atomic emission spectrometry. The results showed that the granule could be round and smooth after cupellation at 880 ℃ when the dosage of lead foil was 20 g. Through the homogeneity tests of granule dividing, it was proved that the distribution of gold, silver, platinum, and palladium in the granule was uniform. An appropriate amount of granules could be randomly sampled for replenishing silver. The effective replenishing and correction of silver could be realized when the correction coefficient was 1.01 which were determined by cupellation coefficient method. The contents of gold, silver, platinum, and palladium in gold residue samples were determined according to the experimental method. The results were consistent with those obtained by standard method of YS/T 3027.1-2017 for determination of gold, standard method of YS/T 3027.2-2017 for determination of silver, inductively coupled plasma atomic emission spectrometry for determination of platinum, and standard method of YS/T 955.2-2014 for determination of palladium. The relative standard deviations (RSDs, n=7) were between 0.11% and 3.6%, and the recoveries were between 95% and 104%.
刘芳美. 火试金重量法结合电感耦合等离子体原子发射光谱法测定分金渣中金银铂钯[J]. 冶金分析, 2022, 42(3): 26-32.
LIU Fangmei. Determination of gold, silver, platinum and palladium in gold residue by fire assay gravimetric method combined with inductively coupled plasma atomic emission spectrometry. , 2022, 42(3): 26-32.
