ICP-AES测定等离子熔炼合金中的铂、钯和铑

摘要

建立了一种以碱熔-碲共沉淀分离、电感耦合等离子体发射光谱(ICP-AES)测定等离子熔炼合金样品中铂、钯和铑含量的方法.研究了样品处理和测定条件.结果表明,样品与过氧化钠混匀,在730℃马弗炉中保温25 min后,熔融物可用稀盐酸完全浸出;在盐酸介质中,加入碲溶液和二氯化锡溶液微沸30 min,所得铂、钯和铑共沉淀充分;在恒定条件下,对铂、钯和铑含量为0.5~7.0、2.0~40.2和0.2~7.0 g/kg的样品,测定相对标准偏差(RSD)分别为0.44%~1.52%、0.58%~1.06%和0.61%~1.98%,加标回收率分别为99.4%~101%、99.1%~100.5%和98.3%~101%.%An ICP-AES method was established for determination of platinum, palladium and rhodium contents in the Fe-PGM alloy produced from plasma smelting process. Prior to ICP-AES measurements, the alloy was first pretreated by alkali fusion and then by tellurium co-precipitation separation. The conditions for the sample preparation and determination were investigated and optimized. When the alloy was fused with sodium peroxide in the muffle furnace at 730℃ for 25 min, the resulting melt could fully be dissolved in diluted hydrochloric acid. Slightly boiling the solution for 30 min after the addition of the tellurium reagent and SnCl2 would enhance the precipitation of platinum, palladium and rhodium. Under given conditions and for the Fe-PGM alloy containing 0.5~7.0 Pt, 2.0~40.2 Pd, and 0.2~7.0 Rh in g/kg unit,RSD (n=7~9) and the recovery of standard addition were found to be 0.44%~1.52%, 99.4%~101% for Pt, 0.58%~1.06%, 99.1%~100.5% for Pd, and 0.61%~1.98%, 98.3%~101% for Rh, respectively.