Determination of molybdenum in rocks by atomic absorption spectrometry with electrothermal atomization after its separation with α-benzoinoxime

Abstract

A method has been worked out for a sensitive and accurate determination of molybdenum in rocks in contents of the order of 10-1 g/t. The sample is decomposed with acids and molybdenum is separated from practically all other elements by extraction with α-benzoinoxime from solution of 1.5 M hydrochloric acid and 0.13 M tartaric acid into chloroform, and determined in the extract by AAS with electrothermal atomization. The quantitativeness of the extraction has been examined and the optimum conditions for the determination in a graphite furnace have been established. The effects of chloroform and of the graphite atomizer on the signal of molybdenum have been investigated, and the accuracy of the method has been tested on GXR geochemical standards.