Rapid, high-purity chemical separation of molybdenum from iron meteorites for isotopic analysis by using thermal ionization mass spectrometry

Abstract

A chemical procedure has been developed, which combines both solvent extraction and anion exchange, so that microgram amounts of Mo can be cleanly, rapidly and efficiently separated from gram amounts of iron meteorites. Particular attention was directed to the complete separation of Mo from Zr and Ru. The isotopic abundance ratios of Mo can subsequently be determined with high accuracy by using thermal ionization mass spectrometry. The experiments indicate that the behaviour of Mo during solvent extraction and anion exchange is considerably different from that reported previously. In particular, it was found that there is a very narrow range of HCI concentrations within which it is possible to separate Mo from Fe by solvent extraction. The reproducibility and recovery of the method were examined by using inductively coupled plasma atomic emission spectrometry.