Catalytic oxidation of toluene and p-xylene using gold supported on Co ₃O₄ catalyst prepared by colloidal precipitation method

Gold supported on cobalt oxide has been successfully synthesized through a colloidal precipitation method and tested in toluene and p-xylene total oxidation. It has been demonstrated that the catalytic activity of Au/Co ₃O₄ for toluene and p-xylene oxidation is much higher than that of Au/Al₂O₃ and Au/MgO in spite of its lower BET surface area and larger gold crystalline size. The enhanced catalytic activity in toluene and p-xylene oxidation has been linked to a high concentration of superficial electrophilic oxygen species and oxygen vacancies, which may be originated from a strong interaction in the colloidal Au-Co₃O ₄ system.