Selective catalytic reduction of NO with NH3 over iron titanate catalyst: Catalytic performance and characterization

A novel iron titanate catalyst prepared by conventional co-precipitation method showed excellent activity, N2 selectivity and H2O/SO2 durability in the selective catalytic reduction (SCR) of NO with NH3. The influence of precursors and preparation methods on the catalyst structure and activity was comprehensively investigated. Iron titanate catalyst prepared using titanium sulfate as Ti precursor was favorable for the high activity and selectivity, comparing with that using titanium tetrachloride as precursor and Fe2O3/TiO2 loaded type catalyst. Especially, the best iron titanate catalyst showed good activity in a temperature window of 200–350 °C with the NOx conversion above 90% in the absence of H2O, which was 50–150 °C lower than those of other known Fe-based catalysts. Iron titanate crystallite with specific Fe–O–Ti structure was found to be the main active phase. The interaction between iron and titanium species in atomic scale led to an enhancement of oxidative ability of Fe3+, which was beneficial to the SCR reaction.