Accelerating effect of ZrO2 doping on catalytic performance and thermal stability of CeO2–CrOx mixed oxide for 1,2-dichloroethane elimination

Abstract A series of CeO 2 –ZrO 2 –CrO x mixed oxides with different Ce/Zr molar ratios were synthesized by co-precipitation method and tested for deep catalytic oxidation of 1,2-dichloroethane (DCE), as one of the typical chlorinated VOCs pollutants. The results show that the addition of proper amount of ZrO 2 significantly improves the catalytic activity of CeO 2 –CrO x , and only very slight C 2 H 3 Cl is detected as the sole byproduct in the oxidation process, due to the relative concentration of oxygen vacancies and Cr 6+ species on the catalysts being increased. Moreover, though aged at 700 °C for 4 h, the catalytic performances and the thermal stability of the aged CeO 2 –ZrO 2 –CrO x catalysts can be maintained to a large extent, especially for the CZCr catalyst (atom molar ratio Ce:Zr:Cr = 2:2:1). It may be related to that smaller Zr and Cr ions are embedded into CeO 2 lattice to form solid solution and thus the structure stability being maintained. Besides, the catalysts exhibit good durability for 1,2-dichloroethane oxidation during the long-term continuous test, whether in dry air or in the existence of water and non-chlorinated VOCs, indicating that the CeO 2 –ZrO 2 –CrO x catalysts deserve more attention and may be potential for industrial application.