Pd-based catalysts promoted by hierarchical porous Al2O3 and ZnO microsphere supports/coatings for ethyl acetate highly active and stable destruction

Developing economical and active materials is of great significance for VOC purification. Here, hierarchical porous Al2O3 and ZnO microspheres (Al2O3-pm and ZnO-pm) were synthesized by a facile hydrothermal strategy. The urchin-like Al2O3-pm and flower-like ZnO-pm possess high specific surface area (especially; external surface area) obviously boost the dispersion of Pd with 29.3 % and 30.1 % over Pd/Al2O3-pm and Pd/ ZnO-pm, respectively, over 3.4 times higher than those of commercial Al2O3- and ZnO-supported counterparts. Pd/Al2O3-pm possesses excellent activity and CO2 yield in ethyl acetate (EA) degradation, with TOF reaches 7.76 x 10(-3) s(-1) at 160 degrees C under GHSV of 50,000 h4. Moreover, Pd/Al2O3-pm exhibits satisfied performance in EAcontained binary VOCs oxidation and has high long-term stability under both dry and humid conditions. Both Pd sites and Bronsted acid sites participated in reaction process and initially react with EA to form ethylene and ethanol, respectively. Larger amount Bronsted acid sites over Pd/Al2O3-pm promote ethanol formation and C-C

Automated summary

The hierarchical porous Al2O3 and ZnO microspheres synthesized for Pd loading show excellent performance in VOC purification, particularly in ethyl acetate degradation and binary VOC oxidation, with high activity and stability.