Biomass-Modified Au/TS-1 as Highly Efficient and Stable Nanocatalysts for Propene Epoxidation with O2 and H2

Although supported Au catalysts have been frequently used for propene epoxidation in O-2 and H-2, long-term stability is still a major challenge for industrial applications. This work presents the fabrication of diverse Au/TS-1 catalysts via a simple biomass-mediated immobilization approach, wherein Au precursors were in situ reduced by using an extract solution from biomass. The effects of Au loading, calcination temperature, and reaction operation conditions (e.g., reaction temperature and time on stream) on the catalytic performance of Au/TS-1 were systematically studied. Under the optimal reaction parameters, propene oxide (P0) formation rate of 187 gpo kg(cat).(-1) h(-1), PO selectivity of 73.7%, and propene conversion of 15.4% were obtained. Importantly, the obtained Au/TS-1 catalyst also exhibited excellent stability even after 850 h on stream, which was much better than the previously published results (<100 h). It was believed that the existence of residual biomass (content <1 wt %) on the catalyst surface may not only prevent Au particles from agglomeration but also inhibit the formation of carbon deposition from reaction intermediates.