COMPARISON OF ACID DIGESTION TECHNIQUES TO DETERMINE HEAVY METALS IN SEDIMENT AND SOIL SAMPLES

Four acid digestion procedures were applied to certified samples to offer a proper method for determination of Cr, Cu, Pb and Zn in soils and sediments. EPA’s Acid Digestion Procedure 3050B and three low pressure power microwave heating programmes modified in this study were tested by using two standard materials; Estuarine Sediment-1646A and San Joaquin Soil-2709. Short digestion time, less acid consumption, and high extraction efficiency were noted as the advantages of microwave digestion procedures. According to the results, San Joaquin Soil was efficiently extracted with the second microwave heating programme named as P2 (84.4% Cr, 96.9%Cu, 102.3% Pb, 90.1% Zn)  where Estuarine Sediment gave the most accurate results (99.8% Cr, 103.9% Cu, 97.4% Pb, 96.3% Zn ) with the third extraction procedure (P3).Keywords: acid digestion, heavy metal,  microwave extraction, sediment, soil

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