Validation of an Arsenic Sequential Extraction Method for Evaluating Mobility in Sediments

摘要: Arsenic (As) mobility and transport in the environment are strongly influenced by arsenic's associations with solid phases soil sediment. We have tested a sequential extraction procedure intended to differentiate following pools of phase arsenic:  loosely adsorbed As; As coprecipitated metal oxides or amorphous monosulfides; crystalline iron (oxyhydr)oxides; oxides; pyrite; sulfides. Additions As-bearing wetland riverbed sediment subsamples were quantitatively recovered extractants procedure:  on goethite, 1 M NaH2PO4; arsenic trioxide (As2O3), 10 HF; arsenopyrite (FeAsS), 16 N HNO3; sulfide, HCl, 50 mM Ti-citrate-EDTA, orpiment (As2S3), hot concentrated HNO3/H2O2. Wet from both highly contaminated peat less As-rich sandy used test p...