石墨炉原吸收光谱法测定化探样品中超痕量铂钯

The application of graphite furnace atomic absorption spectrometry to determination of ultra-trace platinum and ultra-trace palladium in rock ore

研究了苯基硫脲—正辛醇体系萃取石墨炉原子吸收光谱法测定化探样品中超痕量铂钯的方法。确定了仪器的最佳条件,并从介质酸度、萃取时间和体积、苯基硫脲的浓度、萃取剂体积和干扰情况等方面进行了详细的考察。样品经王水溶解,液相萃取,以有机相进样测定。铂、钯检出限分别为0.5×10^(-9)和0.1×10^(-9)。对含铂14.7×10^(-9)和钯15.2×10^(-9)的矿样重复取样溶矿测定8次,其相对标准偏差分别为6.0%和4.7%,测试质量较好。

This paper presents a method for the determination of ultra-trace platinum and ultra-trace palladium in rock ore by graphite furnace atomic absorption spectrometry after extraction from phenylthiourea-octanol. The conditions for extraction of platinum and palladium,the interference of co-existing ions and the optimum instrumentation conditions were studied. The liquid phase extraction was conducted after the sample was dissolved by aqua regia,and then the sample test was measured in the organic phase. The detection limit of platinum and that of palladium were 0.5×10^-9 and 0.1×10^-9. The relative standard deviations of the method were 6.0% and 4.7%,respectively,for eight samples with platinum 14.7×10^-9 and palladium15.2×10^-9 from the repeated sampling and dissolution. The relative standard deviations are 6.0% and 4.7% respectively,showing relatively good analytical quality.