CO2 reforming CPO reactor Co-Zn/H-Beta Cu/SSZ-13 DeNOx Liquefied natural gas Low-temperature catalyst MW incinerator NH3-SCR NO removal NOx reduction by C3H8 Ni-catalyst Rh Rh catalysts SEM SO2 poisoning SO3 Selective Catalytic Reduction (SCR) TEM V2O5-WO3/TiO2 catalysts aluminum sulfate ammonium sulfates barium carbonate biogas catalyst catalyst deactivation catalyst durability catalytic methane combustion coke deposition copper