Effects of properties of manganese oxide-impregnated catalysts and flue gas condition on multipollutant control of Hg0 and NO

Multipollutant Control (MPC) of Flue Gas from Stationary Sources Using SCR Technology: A Critical Review

“…V-Ti catalysts with V 2 O 5 as the main active component, anatase TiO 2 as the support, and MoO 3 /WO 3 as auxiliary agents are widely used in the SCR technology. , However, SCR catalysts need further development to meet the requirements of the simultaneous removal of various pollutants. Ce doping was shown to reduce the dispersion of the active components of a V-Ti catalyst.…”

“…The Ce 4+ + Cu + ↔ Ce 3+ + Cu 2+ redox cycle can significantly improve the oxidizing capacity for Hg 0 . The mutual conversion between Mn 4+ and Mn 3+ in a Mn-doped V-Ti catalyst provided abundant lattice oxygen for Hg 0 oxidation . A low concentration of SO 2 (≤200 ppm) promotes the Hg 0 oxidation on MnO x -V 2 O 5 -WO 3 /TiO 2 catalyst, while a high concentration of SO 2 (≥500 ppm) exhibits an inhibitory effect.…”

“…This is mainly attributed to the promotion caused by the conversion of SO 2 to SO 3 and the inhibition caused by the competitive adsorption between SO 2 and Hg 0 . Besides, NO and NH 3 also exhibit inhibitory effects on the Hg 0 oxidation . Some researchers have comprehensively investigated the Hg 0 oxidation activity of V-Ti catalysts doped with different transition metals, showing that in the same atmosphere, the activity of the modified SCR catalysts follows the order Ce/SCR > Cu/SCR > Fe/SCR ≈ Mn/SCR > Ni/SCR > SCR .…”

“…The addition of O 2 can supplement the chemisorbed oxygen consumed during Hg 0 oxidation. − It is worth noting that O 2 does not affect the Hg 0 oxidation alone but participates in this process through the synergistic effect of HCl, SO 2 , and NO. SO 2 can react with Hg 0 to generate HgSO 4 but occupies the active sites of the SCR catalyst and engages in adsorption competition with Hg 0 and HCl, which inhibits Hg 0 oxidation to a certain extent . Besides, H 2 O also exhibits competitive adsorption on the SCR catalyst active sites, thereby preventing the adsorption of active substances that promote Hg 0 oxidation.…”

Kinetic mechanism on elemental mercury adsorption by brominated petroleum coke in simulated flue gas

“…The results were consistent with the research results reported by other researchers, An et al reported that the promotion of 800 ppm SO 2 was reduced on elemental mercury adsorption by active coke, 42 Chiu reported that mercury removal changed from promotion to inhibition with SO 2 concentration of 500 ppm by MnO x /SCR catalyst. 43 …”