CePO4 Catalyst for Elemental Mercury Removal in Simulated Coal-Fired Flue Gas

CePO 4 catalyst (termed Ce–P–O) was for the first time employed to capture elemental mercury (Hg 0 ) under simulated coal-fired flue gas conditions. As compared with commercial SCR catalyst (i.e., V–W–Ti), the Ce–P–O catalyst showed a much better performance in Hg 0 removal. The high Hg 0 adsorption capacity, abundant active oxygen species, and excellent SO 2 poisoning resistance account for the performance of the Ce–P–O catalyst. When the catalyst was subjected to individual flue gas component conditions, it was found that the presence of NO can significantly improve the Hg 0 removal efficiency over the Ce–P–O catalyst; however, HCl did not show promotion effect. It is proposed that the former occurs because the generated NO 2 (originated from NO oxidation) could react with Hg 0 ad-species (e.g., Hg 2 O), regenerating the HgO and hence enhancing the Hg 0 chemisorption. The latter was found to be due to the absence of the Deacon reaction over the catalyst.