Selective liquid phase oxidation of ethyl benzene to acetophenone by palladium nanoparticles immobilized on a g-C3N4–rGO composite as a recyclable catalyst

Abstract

In this study, synthesis of acetophenone as a widely used industrial compound was investigated by liquid phase oxidation of ethylbenzene with TBHP as an oxidant in acetonitrile over Pd/g-C₃N₄–rGO as a recyclable catalyst. The hybrid composite of graphitic carbon nitride (g-C₃N₄) and reduced graphene oxide (rGO) was synthesized by a simple wet impregnation method and was used as a support for palladium nanoparticles. The characterization of the Pd/g-C₃N₄–rGO composite was carried out using different techniques such as XPS, FT-IR, X-ray diffraction, FESEM-EDS and mapping, TEM, TGA, ICP-OES, and BET–surface area. The Pd nanoparticles were homogeneously distributed on the hybrid support with reasonable surface area. Moreover, this system revealed a good performance in the production of acetophenone as the main product of oxidation of ethylbenzene under mild conditions with 67% and 97% conversion and selectivity, respectively. In addition, the proposed catalyst also retained its activity and selectivity for acetophenone after 5 runs.