ISSN: 1003-6326
CN: 43-1239/TG

Vol. 27    No. 6    June 2017

Chloride leaching of Pt-Pd concentrates
LIU Zhi-qiang1, 2, ZHOU Xiang-qian1, 2, ZHANG Kui-fang1, 2, QIU Xian-yang1, 2
(Guangdong Province Research Institute of Rare Metal, Guangdong Province Key Laboratory of Rare Earth Development and Application, Guangzhou 510650, China)
Abstract: Mineralogy of a Pt-Pd concentrate was characterized and the results show that the Pt-Pd minerals in the concentrates are mainly Te-Pt-Pd minerals, S-Pt-Pd minerals, As-Pt-Pd minerals and Sn-Pt-Pd minerals. And the Pt-Pd elements are not uniform distribution in the Pt-Pd minerals. The chloride leaching process was put forward to realize extraction and separation of Pt-Pd in the minerals. Effects of process parameters on Pt-Pd leaching rate were investigated, including HCl concentration, liquid-solid ratio, reaction1 time, reaction temperature, sodium chlorate dosage and sodium chlorate acceleration rate. The optimum technological parameter is determined. The phase of leaching slag was analyzed and the leaching project was optimized. The result shows that the leaching rate of Pt and Pd reaches 92.83% and 99.7% respectively, under the best leaching conditions of 4 mol/L in HCl concentration, 4:1 in liquid-solid ratio, 95 ℃ in temperature, 9h in reaction time, 3.2:1 in liquid-solid ratio of sodium chlorate solution (625 g/L) dosage and concentrate quality (80 mL:25 g), and 12 mL/h in acceleration rate. Phase analysis of leaching slag shows that a part of Pt that cannot be leached is fully or partially contained by minerals such as talc, albite and rutile, resulting in the difficulty of Pt leaching.
Key words: platinum; palladium; Pt-Pd concentrate; chloride leaching
Superintended by The China Association for Science and Technology (CAST)
Sponsored by The Nonferrous Metals Society of China (NFSOC)
Managed by Central South University (CSU)