Determination of beryllium in coal fly ash by electrothermal atomic absorption spectrometry

Abstract

Separation of the analyte using a β-diketo liquid chelating exchange (LCE)(C₉H₁₉COCH₂COCH₃) and subsequent determination by electrothermal atomic absorption spectrometry (ETAAS) is described for the determination of beryllium in coal fly ash emitted from coal fired power stations. The conditions for the separation and preconcentration of beryllium, e.g., pH, solvent, shaking time and kinetics of the extraction and the effects of various ions have been optimized. Quantitative extraction (100%) of beryllium with LCE occurs in a cyclohexane medium at pH 9.5, the extracted species being [Be(C₉H₁₉C)(O)CH C(O)CH₃]. Direct analyses of the fly ash samples using ETAAS, and of standard reference materials, always gave higher results than the proposed method due to the presence of various interfering metals. The reliability of the method has been demonstrated by the recoveries (97.4–98.4%) of standard additions of beryllium to fly ash sample solutions.