Determination of tellurium in a nickel-based alloy by flow injection vapor generation inductively coupled plasma mass spectrometry

Abstract

A simple and inexpensive laboratory-built vapor generator was used with inductively coupled plasma mass spectrometry (ICP-MS) for the determination of Te in nickel-based superalloys. Various reagents were tested as the masking agent for the alleviation of transition metals interferences. After evaluation, a mixture of 0.1% m/v L-cysteine and 0.5% m/v thiourea was used as the masking agent. The applications of vapor generation (VG) ICP-MS alleviated the non-spectroscopic interferences and sensitivity problems encountered when a conventional pneumatic nebulizer was used for sample introduction. The concentration of Te was determined by the isotope dilution method and standard additions method. The isotope ratio of Te was calculated from the peak areas of each injection peak. The repeatability of the peak areas and isotope ratio determinations of five consecutive injections of 5 ng ml−1 Te solution was 2.1% and 2.3%, respectively. This method has a detection limit of 27 ng g−1 for Te in a nickel-based alloy. This method was applied to determine Te in NIST Tracealloy SRM 897–899. The results agreed satisfactorily with the reference values. Accuracy was better than 5%. The precision between sample replicates was better than 8% for all the determinations.