Effect of physical mixing of solid components on the epoxidation of propylene over gold catalysts

PETR 104

Jun Kawahara1, Noriyasu Hamakawa2, Jiahui Huang1, Susumu Tsubota2, and Masatake Haruta, haruta-masatake@center.tmu.ac.jp1. (1) Department of applied chemistry, Tokyo Metropolitan University, Minamiosawa1-1, Hachioji, Tokyo, 192-0397, Japan, (2) Research Institute for Innovation in Sustainable Chemistry, National Institute of Advanced Industrial Science, Onogawa 16-1, Tsukuba 305-8569, Japan
The direct epoxidation of propylene with molecular oxygen alone is an ideal reaction in view of green chemistry, however, a more feasible route to propylene oxide(PO) is to add hydrogen to a mixture of propylene and oxygen in the presence of supported gold catalysts. Major constraints in this route are low conversion and catalyst deactivation. Our first attempt to solve these problems was to reduce the numbers of hot spots in the catalyst bed by adding SiC powder which had high thermal conductivity. As a result, SiC improved not only PO selectivity and H2 efficiency but also propylene conversion. Then, in order to clarify whether propylene epoxidation with dioxygen and dihydrogen is composed of two steps; hydrogen peroxide synthesis over gold nanoparticles and epoxidation of propylene at isolated Ti4+ sites, Au/SiO2 catalysts (generation of H2O2) were physically mixed with titanosilicates including Ti4+ site(epoxidation process).
 

Poster Session
9:00 AM-11:00 AM, Wednesday, August 22, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Petroleum Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007