A Green CeO2 WO3/TiO2 Medium-Low Temperature de-NOx Catalyst for Selective Catalytic Reduction of NOx with NH3

摘要

A series of CeO2-WO3/TiO2 catalysts were synthesized by the co-precipitation method and used for selective catalytic reduction (SCR) of NO with NH3 under medium-low temperature conditions with metatitanic acid as Ti source. A more reasonable weight ratio of CeO2 and WO3 was explored. The catalytic activity enhanced with the increase of cerium content, but the catalytic activity changed slightly in the temperature range of 240°C to 400°C when the cerium content exceeded 15%. Tungsten could enhance the sulfur resistance by adjust- ing the degree of crystallization, acidity in the SCR process. When the weight ratio of CeO2 to WO3 was 15: 8, the conversion rate of NO was more than 90% in the temperature range of 240°C to 440°C. For 15%CeO2-8%WO3/TiO2 catalyst, the NO conversion was maintained around 84% when the mixed gas was introduced SO2. At the same time, we have optimized the selection of carriers, metatitanic acid as a carrier was better than titanium dioxide.