Solvent-free aerobic selective oxidation of benzyl alcohol over La-Co bimetallic catalyst: A kinetic study

It is desirable but challenging to explore non-noble metal based catalyst for the solvent-free aerobic oxidation of benzyl alcohol to benzaldehyde. LayCo1Ox was prepared through a co-precipitation method, which exhibited excellent catalytic performance for titled reaction with a yield of 73.1% and selectivity of 99.6%. Introduction of La in the Co3O4 can modify the electronic property of Co, improving the surface Co3+ content and enhancing the activity. The synergistic effects of La and Co in the bimetallic catalysts are kinetically discussed. In addition, the kinetic and experimental studies revealed that the generated water favors the selectivity but suppresses the activity for the titled reaction. It is found that good activity and excellent selectivity for the (heterocyclic)aromatic alcohols aerobic selective oxidation over the bimetallic catalyst were obtained. [Display omitted] •La-Co bimetallic catalyst can yield 73.1% benzaldehyde with the selectivity of 99.6% under solvent-free condition.•Kinetic study indicates that the titled reaction is a consecutive reaction with both steps of a first order.•Synergistic effect between La and Co kinetically contributes to the excellent catalytic performance.•Water is kinetically and experimentally revealed to favor the selectivity but disfavor the activity.