Adsorption and reduction of hexavalent chromium on magnetic greigite (FeS)-CTAB: leading role of Fe(ii) and S(-ii).

In this study, a facile one-step route was used to synthesize a novel magnetic mesoporous greigite (FeS)-CTAB composite, which was utilized to remove hexavalent chromium (Cr(vi)). The optimized FeS-CTAB composite with a CTAB dosage of 0.75 g possessed the maximum specific surface, showing the highest Cr(vi) adsorption capacity of 330.

Preparation and application synthesis of magnetic nanocomposite using waste toner for the removal of Cr(vi).

In this study, a novel magnetic nanocomposite was prepared using waste toner (WT) through high temperature decomposition, and calcination was conducted in different atmospheres (air, ammonia, and vacuum). WT calcined in ammonia (WT(NH)), and it was then utilized as an efficient absorbent for the reduction of Cr(vi) in aqueous solutions; a batch experiment with different conditions was performed to investigate its Cr(vi) removal ability. The effects of two pH-regulating acid (HCl and HSO) treatments were also studied.