Comparison of NaOH fusion and microwave oven digestion for the determination of arsenic and selenium in coal fly ash reference material using hydride generation-atomic absorption spectrometry

A method is described for the determination of As and Se in coal fly ash standard reference material SRM NIST-1633b, using microwave oven digestion with a Parr bomb and hydride generation. The results obtained with this preocedure agree well with the certified values. The method is further compared with the NaOH fusion dissolution procedure. The limit of detection for As and Se was 0.25 ng/mL and 0.8 ng/mL, respectively. The characteristic concentration, corresponding to 0.0044 absorbance signal, was 0.35 ng/mL for As and 0.88 ng/mL for Se.