Multi-element analysis of ferrotungsten by inductively coupled plasma atomic emission spectrometry

Abstract

An inductively coupled plasma atomic emission spectrometry (ICP—AES) procedure has been developed for the determination of aluminium, cobalt, chromium, copper, manganese, molybdenum, nickel, silicon, titanium and vanadium in ferrotungsten. The sample is dissolved by a combination oxalic acid and hydrogen peroxide and the decomposition is completed with a mixture of sulphuric and phosphoric acids in a PTFE vessel without application of hydrofluoric acid. In this way silicon is quantitatively converted into a solution form. No separation of elements from the matrix is required. Calibration graphs have been prepared using synthetic standard samples and verified by means of the Czechoslovak standard ferrotungsten and analysed ferrotungsten samples. For comparison, the samples were analysed by flame atomic absorption spectrometry. The silicon content was also verified by gravimetric and titrimetric methods. The results and accuracy of the method are discussed.