Determination of chromium in steel by atomic absorption spectrometry using a direct chelate volatilisation method

The volatilisation of chromium as its acetylacetonate and subsequent atomisation in a silica tube, heated with an air-acetylene flame was used for the determination of chromium in steel. The proposed method gives a detection limit (DL) of 0.2 ng (DL =kσ/s) and the reproducibility, expressed as the relative standard deviation, is of the order of 4%. The conditions of chelate formation and the matrix effects were investigated. This method eliminates the interference effect produced by iron and acids on the chromium signal.