Co-SBA-15-Immobilized NDHPI as a New Composite Catalyst for Toluene Aerobic Oxidation

A new composite catalyst was constructed by immobilizing active site N,N-dihydroxypyromellitimide (NDHPI) on the co-catalyst Co-doped mesoporous sieve SBA-15 through the chemical bond with the 3-(glycidoxypropyl) trimethoxysilicane used as the silylation agent. The catalyst was characterized by various means. The new catalyst showed significantly higher activity in toluene aerobic oxidation at 90 degrees C with acetonitrile as a solvent or under solvent-free condition compared with the NDHPI and co-catalyst independent system. The effects of the reaction conditions such as temperature, oxygen pressure, catalyst amount on the toluene oxidation over the immobilized catalyst were also investigated. After reuse for three times, the composite catalyst kept the activity without loss of Co from SBA-15.