Promoting the low temperature activity of Ti-V-O catalysts by premixed flame synthesis

Ti0.9V0.1O2−δ catalysts were prepared by flame synthesis to improve low temperature activity for selective catalytic reduction (SCR) of NO with ammonia. The influence of different synthesis conditions (precursor concentration and axial distance of stagnation plate) was investigated. The activities of these catalysts were performed by temperature programmed reaction (TPR). These catalysts were characterized by surface area measurement, XRD, TEM, Raman spectroscopy, XPS, H2-TPR and NH3-TPD. The results showed that the Ti0.9V0.1O2−δ catalysts synthesized with 304 ppm precursor concentration, exhibited small particle size and high SCR activity. The particle size of Ti0.9V0.1O2−δ generally increased as the axial distance of stagnation plate. The samples prepared with stagnation plate placed 20 mm beneath the nozzle were most active, which might be caused together by strong interaction between vanadia species and titania surface, high redox properties and abound Brønsted acid sites. Sample Ti0.9V0.1O2−δ (304-20) showed excellent H2O-resistant performance.