Nano-sized gold particles dispersed on HZSM-5 and SiO2 substrates for catalytic oxidation of HCHO

Au catalysts supported on HZSM-5 and SiO2 prepared by a deposition-precipitation (DP) method with ammonia as the precipitant were very active for HCHO complete oxidation at room temperature under humid air. The treatment atmosphere exerted significant effects on the catalytic performance. The catalysts treated in H-2 had better Au dispersions and smaller Au particle sizes than those treated in air, which were crucial for high reactivity. Both catalysts deactivated at high GHSV (600,000 ml g(-1) h(-1)), due to the growth of Au nanoparticles during the reaction, as well as the accumulation of surface species such as formate intermediates on the catalyst. Our results suggested that small Au particle size and strong metal support interaction were the key factors for the high activity for HCHO oxidation over Au supported on silica-based materials. (C) 2016 Elsevier B.V. All rights reserved.