LAUSR

The exhaust gas contains harmful products, including fuel-additive elements such as compounds of sodium, which cause dramatic catalyst deactivation of catalysts during selective catalytic reduction (SCR) of NO with NH3. There is an increasing demand to synthesize alkali poisoning-resistant catalysts for industrial NH3-SCR applications. In the present study, the as-synthesized Fe2O3/MoO3/TiO2 exhibits a high degree of resistance toward Na2SO4 poisoning during the NH3-SCR reaction. With 500 μmol g-1 Na+ poisoning, the Fe2O3/MoO3/TiO2 showed approximately 95% (or more) of its original activity throughout the entire temperature rage. Even with 700 μmol g-1 Na+ poisoning, Fe2O3/MoO3/TiO2 still performed well. The 500 and 700 μmol Na+ g-1 loadings dictate that on average, SCR catalysts could be exposed to alkali-rich and highly dusty environments for over 14000 and 20000 hours, respectively. The layered MoO3 building block is used as a binding buffer and sandwiched between the active phase and TiO2 support to provide sufficiently stable binding sites for Na2SO4 poison and to present alkali blocking of the surface active phase. Our findings provide useful information regarding the use MoO3 as a safety buffer for developing functional NH3-SCR catalysts with enhanced alkali-poisoning resistant performance and long lifetimes.