Vanadium-containing mesoporous carbon and mesoporous carbon nanoparticles as catalysts for benzene hydroxylation reaction

Highly ordered mesoporous carbon of body-centered cubic structure was synthesized by the evaporation induced self-assembly method using Pluronic F127 and phenolic resol as the template and carbon source, respectively. Vanadium species were introduced to the carbon support by both co-assembly and impregnation strategies for comparison. Ordered mesoporous carbon nanoparticles of the same body-centered cubic structure were also synthesized via a facile soft-template method, followed by the incorporation of vanadium species via impregnation. The obtained three different series of vanadium-containing carbon catalysts were tested in the direct benzene hydroxylation reaction using H2O2 as an oxidant. The vanadium supporting mesoporous carbon nanoparticles, due to the open framework and short channels for fast reactants diffusion and the easily accessible active vanadium species for reactants activation, exhibited superior catalytic activity to other series of catalysts. Particularly, the 4V/MCN-S catalyst showed the best catalytic performance among the studied catalysts with a benzene conversion of 38.2% and phenol selectivity of 96.1%, along with good stability during five recycles.