Unveiling the lead resistance mechanism and interface regulation strategy of Ru-based catalyst during chlorinated VOCs oxidation

Maintaining stable catalytic performance for chlorinated volatile organic compounds (CVOCs) oxidation in Pb-containing scenarios is an intractable challenge for the industrial application of Ru-based catalysts. Herein, we systematically investigated the effect of Pb poisoning on the activity over various Ru-based catalysts during the CVOCs oxidation and explored the possible Pb resistance mechanism. The source of high Pb resistance was clarified from two aspects: (1) oxygen vacancies on supports (CeO2 or TiO2) captured Pb and firmly locked it in lattice, namely strong capture effect; and (2) the formation of stable Ru-O-M (M = Ce and/or W) bonds weakened the affinity between active Ru sites and Pb, ensuring the preferential deposition of Pb at oxygen vacancies. With the synergistic effect of above factors, the intrinsic activity (mainly strong acidity) of Ru sites in Ru/CeO2 and RuW/TiO2 catalysts was retained, which ensured the efficient dissociation of C-Cl bond and oxidation of CB.