(广东省稀有金属研究所 广东省稀土开发及应用重点实验室,广州 510650)
摘 要: 对某铂钯精矿进行了工艺矿物学分析,确定铂钯矿物主要为碲铂钯矿、硫铂钯矿、砷铂钯矿、锡铂钯矿等矿物,铂钯元素在铂钯矿物中分布均匀。采用直接氯化浸出工艺浸出该矿中的铂钯,考察盐酸浓度、液固比、反应时间、反应温度、氯酸钠用量、氯酸钠滴加速率对铂钯浸出率的影响,确定最佳工艺参数,并对浸出渣进行物相分析,优化浸出方案。结果表明:在最佳条件为盐酸浓度4 mol/L、液固比4:1、反应温度95 ℃、反应时间9 h,氯酸钠溶液(625 g/L)用量与精矿的液固比为3.2:1(80 mL:25 g),滴加速度为12 mL/h;在最优条件下,铂、钯浸出率分别达到92.83%和99.7%。浸出渣物相分析显示,未能被浸出的铂被滑石、钠长石及金红石等矿物完全或部分包裹,导致铂浸出困难。
关键字: 铂;钯;铂钯精矿;氯化浸出
(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