Green synthesis of Au/TS-1 catalysts via two novel modes and their surprising performance for propylene epoxidation

In this communication, we report on the preparation of active Au/TS-1 catalysts via two green modes, namely, sol-immobilization method and adsorption–reduction method by using plant extract. Experimental results manifested that bioreduction Au/TS-1 catalysts exhibited excellent performance in vapor phase propylene epoxidation with H2/O2 mixture, especially in view of the fact that the optimal propylene conversion (12.6%) and H2 efficiency (48.9%) are the highest in data reported so far. To our knowledge, this is the first attempt on the preparation of bioreduction Au/TS-1 catalysts for propylene epoxidation.

We report two novel modes for preparing Au/TS-1 catalysts by using Cacumen Platycladi (CP) extract, namely, sol-immobilization (SI) method and adsorption–reduction (AR) method (see picture). Strikingly, a considerable smaller Au size (~ 2 nm) could be obtained for catalysts via AR method, compared with catalysts via SI method (~ 4 nm). Catalysts prepared by these two methods exhibited high activity and stability for propylene epoxidation with H2/O2 mixture.Figure optionsDownload as PowerPoint slideResearch Highlights
► Au/TS-1 catalysts are prepared by novel bioreduction methods.
► Bioreduction can be realized via sol-immobilization route or adsorption–reduction route.
► Bioreduction Au/TS-1 catalysts exhibit high activity for propylene epoxidation.
► The catalysts can operate with no evidence of deactivation within 48 h on stream.