岩石中痕量镉的分离和纯化

Separation and Purification of Trace Cadmium in Rocks

测定岩石样品中镉同位素比值时,常存在镉含量低、同量异位素(106Pd、108Pd、110Pd、112Sn、113In、114Sn和116Sn)干扰问题;而目前已有分离方法对镉的化学收率较高,对同量异位素的去除率较低:因此,需要开发一种对镉有高收率、对钯和锡有高去除率的分离提纯方法。研究建立了N256-N256-P204三柱法分离提纯镉,经标准岩石样品验证,整个流程对镉的收率大于99%,对钯和锡的去除因子大于4.0×10^3,满足岩石中痕量镉同位素比值测定的要求,特别适用于钯、锡丰度未知样品中镉同位素比值的测定。

When determining the ratio of cadmium isotopes in rock,problems of low cadmium content and interference of isotopes(106Pd,108Pd,110Pd,112Sn,113In,114Sn and 116 Sn)were discovered.However,the existing separation methods have high chemical yield for cadmium but low removal rate for isotopic.Therefore,a separation and purification method with high yield for cadmium and high removal force for palladium and stannum is necessary.A N256-N256-P204 three-column separation method was developed for separation and purification of cadmium in rocks.Verified by standard rock samples,the recovery of Cd is more than 99%and the removal factor of Pd and Sn is more than 4.0×10^3.The separation process meets the requirements of isotope ratio determination of trace cadmium in rocks,and is especially suitable for the isotope ratio measurement of cadmium in some samples with unknown Pd and Sn isotope abundance.