Synthesis of acetophenone from aerobic catalytic oxidation of ethylbenzene over Ti–Zr–Co alloy catalyst: Influence of annealing conditions

Abstract

The aerobic catalytic oxidation of ethylbenzene to produce acetophenone over an effective and robust heterogeneous Ti–Zr–Co has been studied. Under the optimum conditions, a high selectivity of 69.2% to acetophenone was obtained at a 61.9% conversion of ethylbenzene over Ti–Zr–Co catalyst, which is much better than the most results reported with heterogeneous catalysts. The catalytic performance and the active species of Ti–Zr–Co catalyst were discussed based on the changes of conversion and selectivity with varying the annealing temperature and atmosphere. It is confirmed that the surface CoO, Co3O4 species are the active sites, and the bulk structure of the alloy, CoTi2 phase also present a large effect on the catalytic activity in present oxidation. As a cheap, robust and separable catalyst as well as a green oxidant is used, the present work provides a facile and green catalytic process for the oxidation of hydrocarbons.