Novel mesoporous SnCeVOx catalyst modified by amorphous titanium tungsten oxides for highly efficient NH3-SCR

Abstract

It is still difficult to create environment friendly, efficient and stable V-based catalysts for the selective catalytic reduction of NOx with NH3. In this work, amorphous titanium tungsten oxides (TiWOy) modified mesoporous SnCeVO4 (SnCeVOx/TiWOy) is reported as a promising alternative to address this issue. As-prepared SnCeVOx/TiWOy exhibits excellent deNOx activity with wide active temperature window (> 95% NO conversion at 195-430 °C) and high N2 selectivity (>90% at 190-350 °C). Moreover, SnCeVOx/TiWOy delivers remarkably anti-poisoning durability to H2O and SO2, with negligible deNOx activity loss at 215 oC after continuous reaction for 12 h in the presence of 200 ppm SO2 and 5% H2O. This excellent deNOx performance is mainly attributed to the high specific surface area, strong surface acid properties, rich oxygen vacancies, which benefits from the introducing SnO2 into CeVO4 and further modified by TiWOy. In-situ DRIFTs spectra display that SnCeVOx/TiWOy follows both L-H mechanism and E-R mechanism. This construction strategy provides a new insight for the development of efficient deNOx catalysts with superior H2O and SO2 resistance.