Lee Jin-Young, Rajesh Kumar J, Kim Joon-Soo, Park Hyung-Kyu, Yoon Ho-Sung
Metals Recovery Department, Minerals Resources Research Division, Korea Institute of Geoscience & Mineral Resources, Yuesong-gu, Daejeon, South Korea.
J Hazard Mater. 2009 Aug 30;168(1):424-9. doi: 10.1016/j.jhazmat.2009.02.056. Epub 2009 Feb 20.
Liquid-liquid extraction/separation of platinum(IV) and rhodium(III) from acidic chloride solutions was carried out using tri-iso-octylamine (Alamine 308) as an extractant diluted in kerosene. The percentage extraction of platinum(IV) and rhodium(III) increased with increase in acid concentration up to 8 mol L(-1). However, at 10 mol L(-1) HCl concentration, the extraction behavior was reversed, indicating the solvation type mechanism during extraction. The quantitative extraction of approximately 98% platinum(IV) and 36% rhodium(III) was achieved with 0.01 mol L(-1) Alamine 308. The highest separation factor (S.F.=184.7) of platinum(IV) and rhodium(III) was achieved with 0.01 mol L(-1) Alamine 308 at 1.0 mol L(-1) of hydrochloric acid concentration. Alkaline metal salts like sodium chloride, sodium nitrate, sodium thiocyanate, lithium chloride, lithium nitrate, potassium chloride and potassium thiocyanate used for the salting-out effect. LiCl proved as best salt for the extraction of platinum(IV). Temperature effect demonstrates that the extraction process is exothermic. Hydrochloric acid and thiourea mixture proved to be better stripping reagents when compared with other mineral acids and bases.
以稀释于煤油中的三异辛胺（阿拉明308）为萃取剂，从酸性氯化物溶液中进行液 - 液萃取/分离铂（IV）和铑（III）。铂（IV）和铑（III）的萃取率随酸浓度增加至8 mol L⁻¹而升高。然而，在盐酸浓度为10 mol L⁻¹时，萃取行为发生逆转，表明萃取过程中的溶剂化类型机制。用0.01 mol L⁻¹阿拉明308实现了约98%的铂（IV）和36%的铑（III）的定量萃取。在盐酸浓度为1.0 mol L⁻¹时，用0.01 mol L⁻¹阿拉明308实现了铂（IV）和铑（III）的最高分离因子（S.F.=184.7）。使用氯化钠、硝酸钠、硫氰酸钠、氯化锂、硝酸锂、氯化钾和硫氰酸钾等碱金属盐产生盐析效应。氯化锂被证明是萃取铂（IV）的最佳盐。温度效应表明萃取过程是放热的。与其他无机酸和碱相比，盐酸和硫脲混合物被证明是更好的反萃试剂。
