LAUSR

A W-modified Mn–Ti mixed oxide catalyst was prepared by the homogeneous precipitation method, which was applied to the selective catalytic reduction of NO with NH3 (NH3-SCR). The introduction of W could broaden the operation temperature window of Mn0.5TiOx, and the Mn0.5W0.1TiOx showed good SCR activity at 150–350 °C (NOx conversion above 80%). The results of characterization demonstrated that W introduction improved the redox ability, inhibited the separated NO/NH3 oxidation abilities, and provided additional Bronsted and Lewis acid sites. When W was added, less NO oxidation to NO2 possibly led to the inhibition of SCR activity at low temperatures, while the increase of NH3 adsorption and inhibition of NH3 oxidation could contribute to the enhancement of high-temperature SCR activity. Meanwhile, the N2O formation in the NH3-SCR over both Mn0.5TiOx and Mn0.5W0.1TiOx mainly follow the Eley–Rideal mechanism, and the introduction of W inhibited the N2O formation.