Fe–Mn–Ce/ceramic powder composite catalyst for highly volatile elemental mercury removal in simulated coal-fired flue gas

The Fe–Mn–Ce/CP catalyst prepared by the incipient-wetness impregnation method was investigated for elemental mercury (Hg 0 ) removal in simulated coal-fired flue gas . The incorporation of Fe could remarkably enhance the SO 2 -resistance of Fe–Mn–Ce/CP catalyst at low temperature, and the existence of water vapor had negative impact on Hg 0 removal efficiency. More than 95% of Hg 0 could be removed at 100   °C under the conditions of 60   ppm HCl, 3% O 2 ( v/v ), 5% H 2 O ( v/v ) and 400   ppm SO 2 . Hg-TPD results indicated that Hg 0 adsorption amount decreased after the addition of H 2 O or SO 2 . The XPS results revealed that the incorporation of Fe could enhance the contents of high valence Mn x + (i.e., Mn 3+ /Mn 4+ ) and Ce 3+ species in the composite catalysts, which are favorable for the oxidation process of elemental mercury. The surface characteristics were not the primary factor determining the catalytic activity . Overall, the catalytic performance of the Fe–Mn–Ce/CP catalyst was closely related to the Fe 3+ state, high ratios of (Mn 4+   +   Mn 3+ )/Mn 2+ and high content of not fully coordinated cerium species.