Catalytic Performance of Ti~(3+) Self-Doped V_2O_5-TiO_2 Catalysts for Selective Catalytic Reduction with NH_3

摘要

Ti~(3+) self-doping modified V_2O_5/TiO_2 catalyst was prepared by sol-gel and impregnation methods and used for selective catalytic reduction (SCR) of NO_x with NH_3. Results showed that Ti~(3+) self-doped V_2O_5/TiO_2 catalyst performed the better catalytic activity. And X-ray diffraction and scanning electron microscopy were used to evaluate the phase composition and morphology of the prepared catalyst. The effects of calcinations temperature of the support, oxygen concentration, [NH_3]/[NO] molar ratio and the GHSV on the denitration performance were investigated. It was found that more than 80% NO_x conversion was obtained at 210 when the O_2 volume fraction was 5%, the NO concentration was 500 ppm, the [NH3]/[NO] molar ratio = 1 and the GHSV was 23,885 h~(-1). The results showed that the catalytic activity increased first with the increasing of O_2 concentration and [NH_3]/[NO] molar ratio, then remained stable. At the same time, the stability of the catalyst was also studied at the temperature of 210. The reaction continued for 750 minutes, and the catalytic activity remained above 80%, indicating that the catalyst has a good stability. Moreover, the Ti~(3+) self-doped V_2O_5/TiO_2 catalyst also showed good SO_2 and H_2O resistance. Therefore, these findings provide important information to better understand the application of the prepared catalyst.