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Chlorine-containing volatile organic compounds (CVOCs) present in industrial exhaust gas can cause great harm to the human body and the environment. In order to further study the catalytic oxidation of CVOCs, an active site regulated RuOx/Sn0.2Ti0.8O2 catalyst with different Ru precursors was developed. With Dichloromethane as the model molecule, the activity test results showed that the optimization of Ru precursor using Ru colloid significantly increased the activity of the catalyst (T90 was reduced by about 90 °C when the Ru loading was 1 wt%). The analysis of characterization results showed that the improvement of the catalytic performance was mainly due to the improvement of the active species dispersion (the size of Ru cluster was reduced from 3–4 nm to about 1.3 nm) and the enhancement of the interaction between the active species and the support. The utilization efficiency of the active components was improved by nearly doubling TOF value, and the overall oxidation performance of the catalyst was also enhanced. The relationship between the Ru loading and the catalytic activity of the catalyst was also studied to better determine the optimal Ru loading. It could be found that with the increase in Ru loading, the dispersibility of RuOx species on the catalyst surface gradually decreased, despite the increase in their total amount. The combined influence of these two effects led to little change in the catalytic activity of the catalyst at first, and then a significant increase. Therefore, this research is meaningful for the efficient treatment of CVOCs and further reducing the content of active components in the catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel catalysts for CVOCs removal present excellent low-temperature activity and high chlorine resistance. • WO x loading affects the surface species morphology while polymer structure at 10% loading shows the best performance. • The RuO 2 -WO x /Sn 0.2 Ti 0.8 O 2 catalysts exhibit highly stable activity in both dry and wet conditions. • Experimental and computational results prove WO 2 Cl 2 to be the main species for tungsten loss on chlorine poisoned catalysts. • The removal performance of CB, TCE and DCM by the cordierite catalyst is validated. The development of catalysts with high activity, selectivity, and durability is crucial for the catalytic oxidation of chlorinated volatile organic compounds (CVOCs). Although acid-modified supports are widely used in catalysis to improve the catalytic activity at low temperature, the acid sites are easily deactivated by Cl poisoning, and the poisoning mechanism remains unclear. Here, a series of RuO 2 -WO x /Sn 0.2 Ti 0.8 O 2 catalysts were synthesized for dichloromethane (DCM) catalytic oxidation. Spectroscopic characterizations revealed that the loading amount of tungsten oxide highly affects the structure of the surface species and, consequently, the low-temperature catalytic activity. SEM, XRD and DFT calculations elucidated that the loss of tungsten species in the form of WO 2 Cl 2 is the main reason for the catalyst deactivation. By loading RuO 2 , the loss of tungsten species could be effectively avoided via the Deacon reaction. The cordierite catalyst exhibits excellent catalytic activity for the oxidation of different types of CVOCs. [ABSTRACT FROM AUTHOR]