MnOx Supported on Hierarchical SAPO-34 for the Low-Temperature Selective Catalytic Reduction of NO with NH3: Catalytic Activity and SO2 Resistance

The ethanol dispersion method was employed to synthesize a series of MnOx/SAPO-34 catalysts using SAPO-34 with the hierarchical pore structure as zeolite carrier, which were prepared by facile acid treatment citric acid. Physicochemical properties characterized XRD, XPS, BET, TEM, NH3-TPD, SEM, FT-IR, Py-IR, H2-TRP and TG/DTG. NH3-SCR performances evaluated at low temperatures. Results show that etching solution concentration 0.1 mol/L yielded MnOx/SAPO-34-0.1 catalyst ca.15 wt.% Mn loading, exhibiting optimal catalytic activity SO2 tolerance Almost 100% NO conversion over 90% N2 selectivity 120 °C under gas hourly space velocity (GHSV) 40,000 h−1 could be obtained this sample. Furthermore, still higher than 65% when 100 ppm introduced reaction for 4 h. These primarily attributed large specific surface area, high acidity abundant chemisorbed oxygen species provided structure, also increase mass transfer gas. This finding suggests poisoning temperatures can improved controlling morphology catalysts, might supply rational strategy design synthesis Mn-based SCR catalysts.