聚氨酯泡沫塑料富集-电感耦合等离子体质谱法测定地质样品中痕量铂和钯

ICP-MS DETERMINATION OF TRACES OF PLATINUM AND PALLADIUM IN GEOLOGICAL SAMPLES AFTER PRECONCENTRATION ON POLYURETHANE FOAM PLASTIC

以聚氨酯泡沫塑料为吸附剂于静态操作条件下,对痕量铂和钯的选择性吸附分离的方法进行了研究。试验表明,泡塑在3.6～4.8mol·L-1HCl溶液与40g·L-1SnCl2溶液构成的吸附介质中,对铂、钯的吸附性能很好,饱和吸附容量为12.90～19.24mg·g-1,钯平均吸附率为95.81%,铂平均吸附率为98.35%,吸附到泡塑中的铂、钯可用灰化法回收,富集倍数可达100倍。结合电感耦合等离子体质谱法,可用于地质样品中痕量铂、钯的富集分离和测定。方法经标准样品分析验证,铂、钯的测定结果与推荐值吻合,标样及样品分析的RSD≤6.5%(n=12)。

Optimum conditions for the selective adsorption of Pt(Ⅳ) and Pd(Ⅱ) on polyurethane foam plastic under static condition were studied. Saturated adsorption capacities of 12.90~19.24 mg·g^(-1) for Pt(Ⅳ) and Pd(Ⅱ) were obtained from a solution containing 3.6~4.8 mol·L^(-1) HCl and 40 g·L^(-1) SnCl_2. Values of average adsorptivity for Pt(Ⅳ) was 98.35% and for Pd(Ⅱ) was 95.81%. Platinum(Ⅳ) and palladium(Ⅱ) adsorbed were recovered by ashing the foam plastic. A concentration multiple of 100 was obtained by this method. This foamplastic adsorption method was used as a preconcentration treatment of sample solution before the ICP-MS determination of trace amounts of Pt and Pd in geological samples. The feasibility of this method was verified by analysis of standard samples. The results of Pt and Pd obtained by this method were in consistency with the standard values, and the RSD′s (n=12) obtained were ≤6.5%.