Application of high resolution X-ray emission spectroscopy on the study of Cr ion adsorption by activated carbon.

Abstract In this work granular activated carbon has been chosen as an absorbent in order to investigate the Cr(VI) reduced by adsorption experiments. Several batch chromium-sorption experiments were carried out using 0.25 g of granular activated carbon in 50 mL aqueous solution containing approximately 70 and 140 mg L −1 of Cr(VI) and Cr(III), respectively. Cr–Kβ fluorescence spectra of Cr adsorbed in a carbon matrix and Cr reference materials were measured using a high-resolution Johann-type spectrometer. Based on evidence from the Cr–Kb satellite lines, the Cr(VI) reduction process has actually happened during metal adsorption by the activated carbon.