The preparation of hierarchical Pt/ZSM-5 catalysts and their performance for toluene catalytic combustion

The hierarchical ZSM-5 zeolite with tunable mesopore volume was successfully prepared by adjusting the synthesis condition and used as the support for dispersing Pt. The mesopore volume of as-prepared hierarchical ZSM5 zeolite showed the monotonous and positive effect for the Pt dispersion. The toluene catalytic combustion was used to evaluate the performance of as-prepared Pt supported catalysts. The results demonstrated the high performance for catalytic toluene combustion over hierarchical Pt/mZSM-5 catalysts compared with Pt/ZSM-5. In addition, the hierarchical Pt/mZSM-5 catalysts showed better reactant molecular diffusion according to the results of toluene dynamic adsorption experiments. Among all the as-prepared catalysts, Pt/mZSM-5-A8 exhibited best activity that T-90 was 159 degrees C and Ea was 40.0 kJ/mol at 500 ppm toluene and 80,000 mL/ (g . h), and the catalyst showed high stability and catalytic activity after catalytic testing for 20 h at 155 degrees C, which implied a promising catalyst for practical application.