The effects of metal oxide blended activated coke on flue gas desulphurization

Abstract

The objective of this study was to investigate the possibility of using some natural minerals or industrial waste containing some metal oxides to prepare modified activated coke (M/AC) for flue gas desulphurization. The metal oxides, i.e. Fe₂O₃, Co₂O₃, CuO and Ni₂O₃, were used as additives to prepare M/AC by a blending method. The results show that the M/AC could effectively improve desulphurization performance, and the highest sulphur capacity was obtained at 143 mg g⁻¹ for the Ni/AC sample with a blending ratio of 12 wt%, which was higher than that of the blank sample (97 mg g⁻¹). The addition of metal oxides by the blending method could affect the textural properties of M/AC evidently and the influence was different with different metal oxides and blending ratios. On the other hand, M/AC samples have higher contents of oxygen-containing functional groups, with the highest for the Ni/AC sample, and have higher contents of π–π* transition groups, compared with blank activated coke. The metal oxides loaded on the M/AC were mainly transformed to metallic particles during the activation process, and to metal sulfate and partially metal oxides after the desulphurization process.