Novel development of VOx–CeOx–WOx/TiO2 catalyst for low-temperature catalytic oxidation of chloroaromatic organics

Abstract

A novel selective catalytic reduction (SCR) catalyst with high catalytic activity on chloroaromatic organics at lower temperatures (160–180 ℃) is critical for municipal solid waste incineration (MSWI) plants. This study prepares a series of honeycomb-type VO_x/TiO₂ catalysts and finally develops a new low-temperature catalyst with high catalytic activity in eliminating chloroaromatic organics. Based on the conversion efficiency (CE) of 1,2-dichlorobenzene (1,2-DCB) and CO₂ selectivity, the optimal VO_x content of 4.06% (in weight) in VO_x/TiO₂ catalyst is first confirmed. By modifying CeO_x and WO_x, a novel honeycomb-type catalyst of VO_x–CeO_x–WO_x/TiO₂ achieves the highest CE (93.1%–93.6%) and CO₂ selectivity (40.9%–60.7%) at 150–200 ℃. It was found that the CeO_x and WO_x can improve the catalytic activity by enriching the surface content of V and O, increasing the proportion of V⁵⁺ and O_surf, enlarging the supply source of reactive oxygen species and their storage capacity, and accelerating the redox cycle of VO_x, CeO_x, WO_x, and reactive oxygen species. This study can guide the development of monolithic low-temperature catalysts with high catalytic activity in eliminating chloroaromatic organics in MSWI flue gas.