Multielement Determination of Ultratrace Impurities in High Purity Tantalum Metals by Flow Injection/Inductively Coupled Plasma Mass Spectrometry

Abstract

A rapid and sensitive method for the determination of impurity elements in high purity tantalum metals is proposed. Tantalum metals were digested with nitric acid (HNO₃) and hydrofluoric acid (HF). The digested sample solutions were injected into a flow injection system with a cation exchange column. Impurity elements adsorbed were eluted with the mixture of HNO₃ and HF, and then the effluent was introduced into an ICP plasma with conventional pneumatic nebulization. In the present flow injection/ICP-MS system, the detection limits, based on 3 times the standard deviation of the blank, were in the range 0.03 - 6 ng/g for the 16 impurity elements (Li, Na, Mg, Mn, Co, Cu, Zn, Ga, Rb, Sr, Cd, In, Ba, Tl, Pb, and Bi).