Possibilities for the simultaneous preconcentration and flame atomic absorption spectrometric determination of Cr(III) and Cr(VI) using a C18 column and sorption loop

The sorption loop as a preconcentration unit used so far in the low-pressure flow injection (FI) system was combined with the hydraulic high-pressure nebulizer (HHPN) and a high-pressure liquid chromatographic (HPLC) column. Thus, the sorption preconcentration of Cr(VI) can be coupled to a powerful sample introduction method or preconcentration techniques of Cr(III). The subsequent determination of the Cr(VI) content of the samples was carried out by flame atomic absorption (FAAS).