Cr–MnO mixed-oxide catalysts for selective catalytic reduction of NO with NH3 at low temperature

Manganese–niobium mixed oxide catalyst for the selective catalytic reduction of NOx with NH3 at low temperatures

“…V, Cr, Mn, Fe, Co, Ni, Cu) oxides have been investigated in the low-temperature SCR reaction. Among these, Mn-containing catalysts exhibited high catalytic activities, such as MnO x -CeO 2 [5,6], Cr-MnO x [7], Mn/TiO 2 [8][9][10][11][12], MnO x / Ce 0.5 Zr 0.5 O 2 [13], and Mn-Ce/ZSM-5 [14].…”

Sulfur and Water Resistance of Mn-Based Catalysts for Low-Temperature Selective Catalytic Reduction of NOx: A Review

“…Among the metal elements, cerium [24,25], chromium [10], iron [27,28,76], cobalt [29,30], copper [52], nickel [77], and several other elements have drawn the most attention as the mixture or dopant to construct binary metal oxide catalysts with MnOx. CeO2 has been studied extensively due to its good characteristics, such as increasing surface acidity after SO2 poisoning [78,79], high surface area [80,81], good dispersion of MnOx on the surface [45], and the redox shift between Ce 4+ …”

“…Yao et al successfully prepared a series of Mn/CeO 2 catalysts via impregnation using deionized water, anhydrous ethanol, acetic acid, and oxalic acid as a solvent and found that Mn/Ce-OA (oxalic acid) exhibited the best water and sulfur tolerance among all catalysts ( Figure 6) [26]. Chen et al [10] found that the SO 2 tolerance of MnO x was dramatically enhanced by the introduction of Cr due to the formation of CrMn 1.5 O 4 .…”

“…Because of the high working temperature window (300-400 • C), V 2 O 5 -based catalysts have to be placed upstream of the dust removal system and desulfurization units to avoid costly heating of the flue gas, where the catalysts are susceptible to deactivation by dust accumulation and SO 2 poison. Therefore, SCR catalysts that are environmentally friendly and can work at low temperatures (around 250 • C or even lower) urgently need to be developed [9][10][11].…”

Hybrid selective noncatalytic reduction (SNCR)/selective catalytic reduction (SCR) for NOx removal using low-temperature SCR with Mn-V2O5/TiO2 catalyst

“…Research on hybrid SNCR/SCR process has been a trend to cut down the cost of business installation and operation (Roy et al, 2008;Wu et al, 2008;Chen et al, 2010;Koh and Park, 2013). Gullett et al (1994) investigated on the optimal condition of combined process of SNCR and SCR, considering the change in space velocity (SV) during SCR, NH 3 injection quantity, and reaction temperature during SNCR process of pilot-scale combustor using natural gas.…”