Supported nanometric Pd hierarchical catalysts for toluene efficient removal: Catalyst characterization and activity elucidation
Micro/mesoporous composite materials with coke-resistant ZSM-5 and three-dimensional large pore KIT-6 as their micro- and mesoporous components were synthesized using a simple in-situ overgrowth approach. The hydrothermal stability and acidity of the biporous catalysts are significantly enhanced. All composite materials act as powerful catalysts for toluene oxidation. Among them, Pd/ZK-6% shows the highest catalytic activity with 90% toluene decomposition at 203 °C, which is more than 30 °C of temperature reduction comparing with Pd/KIT-6. It could be anticipated that the specific surface area and the acidity has a synergistic effect on the Pd dispersion. Overall, the catalytic activities are primarily correlated to the specific surface area, the support acidity, the Pd dispersion and the toluene adsorption capability.
