The superior performance of a Pt catalyst supported on nanoporous SiC-C composites for liquid-phase selective hydrogenation of cinnamaldehyde

摘要

The monometallic Pt catalyst supported on nanoporous composites containing beta-SiC and amorphous carbon was proved to be active and selective for liquid- phase selective hydrogenation of cinnamaldehyde (CAL) even at room temperature. A TOF of higher than 2400 h(-1) and 80% selectivity to cinnamyl alcohol (COL) were furnished by the Pt/SiC-C catalyst at 25 degrees C. Moreover, the Pt/SiC-C nanocatalyst showed superior performance compared to other Pt catalysts supported on carbon, silica or alumina materials under the same conditions for the tested reaction. Of particular note is that the Pt/SiC-C catalyst can be easily recovered and reused for at least 10 runs without any loss in activity or selectivity. We deduce that there is a strong interaction between Pt nanoparticles and SiC-C composites; so that there are still quite a few Pt species with positive charges on the catalyst surface even after being reduced in an aqueous solution of sodium formate at reflux temperature and pre-treated under a hydrogen flow at 400 degrees C, which would be helpful for preferential adsorption and activation of CAL via electrostatic interaction with the oxygen atoms of the carbonyl group of CAL, and thus COL was the primary product obtained with the Pt/SiC-C catalyst.