Pd/SiO2 Catalysts Prepared via a Dielectric Barrier Discharge Hydrogen Plasma with Improved Performance for Low-Temperature Catalytic Combustion of Toluene

Catalytic combustion is a hot topic both in academic research and in environmental protection. In this work, novel SiO2-supported Pd catalysts (Pd/SiO2-P) were prepared by hydrogen plasma and used in the catalytic combustion of toluene. Characterization results indicated that H-2-plasma treatment could significantly enhance the dispersion of Pd nanoparticles and increase the proportion of Pd-0. Meanwhile, H-2-plasma treatment also enlarged the pore size of the SiO2 carrier compared with that of the traditional high-temperature calcination and reduction technology. As a result, Pd/ SiO2-P showed higher catalytic activity and stability than the traditional Pd/SiO2-R catalyst. Under harsh working conditions [with 1000 ppm toluene in feed and 60,000 mL/(g h)], the T-98 of toluene over 0.5% Pd/SiO2-P decreased obviously from 200 degrees C (over 0.5% Pd/SiO2-R) to 170 degrees C. This work could provide a novel method for the preparation of supported noble-metal catalysts.