Synthesis of Mn/Cu co-doping mesoporous carbon by template method for gas phase mercury removal

Mn/Cu co-doping mesoporous carbon sorbent (MnCu x -C) was synthesized via using hard template method. Thymol blue (C 27 H 30 O 5 S) was used as carbon source and MCM-41 was applied as template agent. Copper nitrate trihydrate (Cu(NO 3 ) 2 ·3H 2 O) and manganese acetate tetrahydrate (MnC 4 H 6 O 4 ·4H 2 O) was in-situ co-doped with carbon source as Cu/Mn metals precursor. Mercury removal on the MnCu x -C sorbent was investigated on a fixed bed experimental apparatus. The physical and chemical characteristics of the MnCu x -C sorbent were investigated by using BET, SEM, FTIR, XRD and XPS, respectively. Combing with mercury programmed temperature desorption (Hg-TPD) and density functional theory (DFT), the mechanism of mercury adsorption on the MnCu x -C sorbent was revealed. The results showed that the synthesized MnCu 0.1 -C sorbent displayed high mercury removal performance at 150℃, which was considered to be a potential sorbent for mercury removal from industrial flue gas. Mn doping on the mesoporous carbon greatly improved the mercury removal ability of sorbent with mercury capture rate increasing from 6 % to 89 %. Doping of Cu can effectively improve the SO 2 tolerance of the MnCu 0.1 -C sorbent for mercury removal. With different concentration of SO 2 existing in flue gas, the MnCu 0.1 -C sorbent still kept high mercury removal ability. O 2 in flue gas promoted mercury removal on the MnCu 0.1 -C sorbent with main product of HgO. In the presence of SO 2 , a small amount of HgSO 4 formed on the MnCu 0.1 -C sorbent. The DFT analysis further displayed that Hg 0 was mainly chemisorbed on the surface of MnCu 0.1 -C sorbent with formation of HgO.