One study also showed that the loss of Hg0 on the Mn–Ce/Ti catalyst can be explained by the M–M mechanism under N2 condition, where Hg0 bonds with lattice oxygen on the catalyst surface to form weakly bonded speciation HgOMnOx−1 or reacts with surface oxygen to form HgO directly . Another study also suggested that E–R, Mars–van Krevelen, first-order, and the power-rate law model can be applied to explain the catalytic Sulfo-NHS-SS-Biotin reactions . Additional works on better comprehending the catalytic oxidation and the interactions between Hg0 and SCR catalysts surface are still greatly needed.
3.2.2. Enhancement of NO and SO2 removal for MnOx-impregnated catalyst
Table 4 shows that raw and MnOx-impregnated catalysts exhibited strong and steady NO reduction activity at 350 °C. MnOx impregnation improved the NO reduction from 77.6 to 91.4% under the flue gas condition. Increasing the MnOx amount was shown to enhance the NO reduction. The impregnated MnOx appeared to form polymeric Bronsted acid surface sites and monomeric Lewis acid sites on the TiO2 bulk structure , which promote the adsorption of NO and NH3 for catalytic reduction. Notably, similar to the results of Hg0 oxidation, NO reduction for MnOx-impregnated catalysts was stable and without significant deactivation during the 900 min test.