Sorption of Arsenic, Bismuth, Mercury, Antimony, Selenium and Tin on Dithiocarbamate Loaded Polyurethane Foam as a Preconcentration Method for Their Determination in Water Samples by Simultaneous Inductively Coupled Plasma Atomic Emission Spectrometry and Electrothermal Atomic Absorption Spectrometry

Abstract

Column solid-phase extraction using dithiocarbamate loaded polyurethane foam was applied to the preconcentration of trace amounts of As, Bi, Hg, Sb, Se and Sn from water samples prior to their measurement by simultaneous ICP-AES and ETAAS. The sorption recoveries of all the analytes were higher than 97% for 150 ml water sample solutions passed through the column with pH ≈ 4.5 and sodium chloride concentration up to 3%. For As, Bi, Hg, Sb and Se, quantitative solid-phase extraction can be achieved over a wide pH range, from 0.5 to pH 5. The combination of the proposed preconcentration method with subsequent simultaneous analyte determination in the methanol eluates by ICP-AES permits the detection of 3 µg l ^{- 1} As and Se, 8 µg l ^{- 1} Bi, 0.12 µg l ^{- 1} Hg, 2 µg l ^{- 1} Sb and 6 µg l ^{- 1} Sn in water samples. ETAAS measurement after dissolution of the sorbed analytes in isobutyl methyl ketone allows the detection of 0.06 µg l ^{- 1} As and Sb, 0.1 µg l ^{- 1} Bi and Sn, 0.08 µg l ^{- 1} Se and 0.3 µg l ^{- 1} Hg.