Schwertmannite矿物对铬酸根的吸附行为

In this study, thermodynamic adsorption characteristic and adsorption species of chromate on synthesized schwertmannite was investigated. The results show that the adsorption of chromate on schwertmannite can be well described with Langmuir adsorption model, with the correlation coefficient greater than 0.99. The pH value corresponding to the largest adsorption amount for chromate is 6.0, and the largest adsorption amount is about 107mg•g-1. However, schwertmannite was difficult to renew after adsorbing chromates and the largest desorption rate of chromates is about 7% from pH 3.0 to 5.0. FTIR spectroscopy results show that chromates are adsorbed on schwertmannite by ion exchanging with sulfate adsorbed on the mineral surface and forming the bidentate binuclear complexes with the mineral surface.