Low temperature hydroxylation of benzene to phenol by hydrogen peroxide over Fe/activated carbon catalyst

A series of Fe-based catalysts were prepared by impregnating activated carbon with the aqueous solution of ferric sulfate. These catalysts were employed to the hydroxylation of benzene to phenol using hydrogen peroxide as the oxidant. Boehm titration and X-photoelectron spectroscopy (XPS) were used to characterize the catalysts. It was found that ferric species were mainly anchored on activated carbon via its interaction with surface carboxylic oxygen group. These supported ferric species was found catalytically active for the titled reaction. A benzene conversion of 19.6%, a phenol yield of 17.5% with a selectivity of 89.3% was obtained under optimized conditions: 303 K, atmospheric pressure, and using acetonitrile as the solvent.

Graphical abstractA series of Fe-based catalysts were prepared, characterized by Boehm titration and XPS, and employed to the hydroxylation of benzene to phenol with hydrogen peroxide under moderate conditions. The surface carboxylic groups on activated carbon were mainly responsible for the ferric species to be anchored, and for the synergistic effect between activated carbon and supported ferric species.Figure optionsDownload full-size imageDownload as PowerPoint slide