Promotion of Ni on Performance of Pd-only Catalyst for Destractive Removal of Volatile Organic Wastes

Pd-Ni / La-Ce-Zr-Al2O3 cordierite monolith catalyst for destractive removal of volatile organic gases was prepared by the step-impregnation method and characterized by H2-TPR, automatic N2 adsorption and desorption, XRD and SEM technologies, and the promotion of Ni on the performance of Pd-only combustion catalyst was investigated. The results show that the presence of Ni improves obviously the catalytic activity and thermal stability of the Pd-only combustion catalyst. The Pd-Ni/La-Ce-Zr-Al2O3 / cordierite monolith catalyst (mPd∶mNi=3∶20) calcined at 800 ℃ performed much better than Pd/La-Ce-Zr-Al2O3 / cordierite monolith catalyst for the deep oxidation of toluene, for example, the light-off temperature of toluene over Pd-Ni catalyst is lower ~25 ℃ than that over Pd-only catalyst, and it has high thermal stability even after pre-treated at 1 000 ℃. Addition of Ni promotes the catalytic activity and thermal stability of the supported Pd-only catalyst by active components highly dispersed on the surface of catalyst and strong metal-support interactions between palladium, nickel and the support.