Posta J, Gáspár A, Tóth R, Ombódi L
Department of Inorganic and Analytical Chemistry, University Kossuth Lajos, PO Box 21, H-4010, Debrecen, Hungary.
Anal Bioanal Chem. 1996 Jun;355(5-6):719-20. doi: 10.1007/s0021663550719.
Methods for the on-line chromatographic preconcentration of Cr(III) and Cr(VI) have been developed. Cr(VI) has been preconcentrated on an RP C18 silica based column with tetrabutylammonium-bromide (TBABr) as ion-pairing agent. Specially for Cr(III) a new and effective preconcentration technique based on the sorption of Cr(III)-ions in a C18 column in presence of KH-phthalate has been developed. The efficiency of sample introduction into the atomic emission spectrometer could be improved by hydraulic high pressure nebulization. For the detection of chromium the acetylene/N(2)O flame has been used as a powerful emission spectrometric source. Applying these steps the detection limit (3sigma) could be improved to 25 pg/mL for Cr(III) and to 20 pg/mL for Cr(VI). The method has been applied for the chromium speciation in natural water samples.
