Combustion of chlorinated VOCs using κ-CeZrO4 catalysts

In this work the application of a redox treatment consisting of a high temperature reduction with 5%H2/Ar in the range 950–1075 °C for 3 h followed by mild oxidation at 550 °C with air was evaluated as a tool for improving the catalytic performance of Ce0.5Zr0.5O2 mixed oxide in the combustion of 1,2-dichloroethane as a model chlorinated compound. Interestingly, after reduction at a temperature as high as 1050 °C, a substantially enhanced redox behaviour was noticed which resulted in a significant promotion of the catalytic activity in comparison with the unmodified parent sample. This active performance was assigned to the formation of a new κ-CeZrO4 phase after redox aging characterised by a markedly increased capacity of providing active oxygen species at low temperatures.