A Sequential Separation Procedure for the Determination of Uranium, Thorium and Their Isotopes in Geological Materials

지질시료 중의 U과 Th 분석 및 자연방사성동위원소 측정을 위한 화학적 분리

  • Received : 1997.03.28
  • Published : 1997.10.25

Abstract

Inductively coupled plasma atomic emission spectrometry(ICP/AES) was used for the determination of uranium and thorium in geological materials. Samples were predecomposed by mixed acid digestion technique. The separation of the uranium and thorium was achieved by systematic solvent extraction with TTA(thenoyltrifluoroacetone) and TOA (tri-n-octylamine) and back extraction into HCl. The results for standard rock sample, NIST SRM 278, showed a good agreement with those certified from NIST as well as found values by other non-destructive techniques. Additional purification for extracted portions was carried out by anion exchange chromatography for measurement of several natural radioisotopes of uranium and thorium by alpha spectrometry.

Keywords

uranium and thorium;systematic solvent extraction