(560fm) The Effect of Polyethylene Glycol Modification on CrOx/TiO2 Catalysts for NO Oxidation

CrO_x was loaded on different amounts of polyethylene glycol modified TiO₂ (CrO_x/yPEG-TiO₂) by impregnation method and successfully utilized for NO oxidation. The structure-property relationships of the catalysts were explored through different characterization techniques including XRD, BET, Raman, XPS, O₂-TPD and NO-TPD. The results pointed out that the polyethylene glycol modification could enhance the interaction between CrO_x with TiO₂. Among these CrO_x/yPEG-TiO₂ (y = 0, 30, 50) catalysts, the CrO_x/50PEG-TiO₂ had the strongest interaction between CrO_x with TiO₂, the strong interaction resulted high content of Cr³⁺. Cr³⁺ was the activate oxygen site and associated with the amount of chemical adsorption oxygen. Meanwhile, CrO_x/50PEG-TiO₂ contained a certain amount of Cr⁶⁺, which was the NO adsorption site. Chemical adsorption oxygen and Cr⁶⁺ participated in the reaction of NO oxidation, and CrO_x/50PEG-TiO₂ exhibited the highest catalytic activity due to the synergy effect between Cr⁶⁺ and chemical adsorption oxygen, which reached 55% at the temperature of 350 °C. Moreover, the CrO_x/50PEG-TiO₂ still exhibited wide activity temperature windows of 225–425 °C and good stability.