Liquid-phase oxidation of benzene to phenol by molecular oxygen over La catalysts supported on HZSM-5

The liquid-phase oxidation of benzene to phenol over lanthanum oxide catalysts (LaOx/HZSM-5) supported on HZSM-5 was studied in the presences of oxygen as an oxidant and ascorbic acid as a reducing regent. LaOx/HZSM-5 effectively catalyzes the formation of phenol at 353 K under the pressurization of oxygen. The LaOx/HZSM-5 catalysts take place no leaching of lanthanum species from the catalysts to acidic solvent. Therefore, it is demonstrated that the supported lanthanum catalysts are stable and reusable for the benzene oxidation even in the acidic reaction solution.