Simultaneous determination of trace concentrations of arsenic, antimony and bismuth in soils and sediments by volatile hydride generation and inductively coupled plasma emission spectrometry

Abstract

Trace amounts of arsenic, antimony and bismuth in soils and sediments are determined simultaneously by an inductively coupled plasma-volatile hydride method after rapid attack with concentrated hydrochloric acid in sealed tubes. The samples are treated with the acid at 150 °C for 2 h in capped test-tubes. After addition of potassium iodide solution, the hydrides are formed by mixing the solution with sodium tetrahydroborate(III) solution in a continuous-flow system, and are swept into the plasma by a stream of argon for determination by atomic-emission spectrometry. Acceptable precision and accuracy are obtained, and the detection limits for all three analytes are about 0.1 µg g^–1. Approximately 200 samples can be analysed by one person in a 2-d cycle.