Insights into the effect of flue gas on synergistic elimination of toluene and NOx over V2O5-MoO3(WO3)/TiO2 catalysts

The impact of the complex flue gas (containing SO2, NO, NH3, O-2 and H2O) on the synergistic elimination of toluene and NOx over over V2O5-MoO3(WO3)/TiO2 in the SCR section was systematic researched for the first time. NO and SO2 proved to be mutually repressive in reaction and competitive in absorption. Moreover, NH3 was identified as the key factor responsible for reducing the COx selectivity in the catalytic oxidation of toluene. It promoted the generation of nitriles and indirectly inhibited the generation of benzoic acid, nitrobenzene, and maleic acid (the product of benzene ring opening). In addition, 16 types of polycyclic aromatic hydrocarbons (PAHs) were detected in the exhaust emissions from the flue gas, among which the content of naphthalene was the highest. The V2O5-MoO3(WO3)/TiO2 catalysts displayed low selectivity and generated a lot of by-products with high environmental risk, even though it had a high VOCs removal rate.

Automated summary

This study systematically investigated the impact of complex flue gas on the synergistic elimination of toluene and NOx over V2O5-MoO3(WO3)/TiO2 catalyst. It revealed that NO and SO2 had a mutual inhibitory effect, and NH3 reduced the selectivity of toluene oxidation. Additionally, multiple polycyclic aromatic hydrocarbons were detected in the exhaust emissions.