Potential Cause for Low Lead and Chromium Recoveries during Acid Extractions

摘要

When high concentrations (> or equal to l00 mg/L) of Pb and Cr (IV) are presenttogether in solution, PbCrO4 precipitates, resulting in losses of these two metals. Moderate acidification with 1-2% HN03 does not prevent precipitation loss. Caution is necessary when preparing standard solutions or handling acidic extracts of environmental samples containing high levels of Pb and Cr, since undetected formation of metal chromates will result in low recoveries of these metals....Acid extraction, Hazardous wastes, Lead paint, Contaminated soils, Lead chromate.