Hydrothermal Glucose Modified C/V-SiO₂ as a Reusable Heterogeneous Catalyst for Benzene Oxidation to Phenol by O₂

Abstract

The C/V-SiO₂ samples were synthesized by the hydrothermal treatment of aqueous glucose and V-SiO₂ that was pre-prepared by a sol–gel process. The samples were characterized by XRD, XPS, EPR, FT-IR, SEM, N₂ adsorption–desorption. The results showed that in the hydrothermal process the V-SiO₂ was covered by a rod-like carbonization material, and a small portion of V⁵⁺ species was reduced to V⁴⁺. The activity of the C/V-SiO₂ in benzene hydroxylation with O₂ was tested. The leaching of V from the C/V-SiO₂ during the reaction was restrained because the surface of the V-SiO₂ was covered with the carbonization material. The phenol selectivity of 100% and benzene conversion of 10.8% over C/V(3.9)-SiO₂ were obtained, and the catalytic performance did not decreased after being recycled three times.

Graphical Abstract

The leaching of V from the C/V-SiO₂ was restrained in the hydroxylation of benzene with O₂ because the surface of V-SiO₂ was covered with the carbonization material.