Study of the Effect of Bi and Ce Doping on the Performance of the VWTi Catalyst for Reduction of Nitrogen Oxides

Graphical The study focuses on the synthesis of SCR catalysts with high activity and excellent alkali resistance. The redox performance and surface acidity of VWTi are enhanced and the atomic valencies is optimized through the doping of Ce and Bi. Therefore, the catalytic activity of the catalyst is significantly enhanced and excellent catalytic activity is maintained even after KCl poisoning. Ce-doped V 2 O 5 -WO 3 /TiO 2 (CeVWTi) and its subsequent modifications have been recognized as effective catalysts for the selective catalytic reduction of NO. Herein, CeVWTi catalysts doped with varying amounts of bismuth sulfate (Bi 2 (SO 4 ) 3 ) were synthesized and evaluated for their activity and alkali resistance. These catalysts were characterized using XPS, BET, SEM, H 2 -TPR, NH 3 -TPD, and XRD techniques. The optimal doping level of Bi 2 (SO 4 ) 3 was 1 wt.%. The NO conversion rate of the catalyst co-doped with Ce and Bi was 71.6% under the reaction conditions of 300 °C, gas hour space velocity (GHSV) = 200,000 h −1 with a gas composition of 550 ppm NO, 550 ppm NH 3 , 5.6% O 2 , and N 2 as the balance. The NO conversion efficiency of the Bi 0.01 CeVWTi catalyst was maintained at 90.7% after the addition of 1 wt.% KCl poisoning under the reaction conditions of 350 °C, GHSV = 200,000 h −1 , 550 ppm NO, 550 ppm NH 3 , 5.6% O 2 , and N 2 as the balance. Characterization showed that, despite the reduction in the specific surface area of the catalyst and some acidic sites due to Bi doping, the redox performance of Bi 0.01 CeVWTi was significantly enhanced. The excellent redox performance was maintained even after KCl poisoning.