Determination of the potential byproduct in the toluene oxidation process by CuMnO_x catalyst on cordierite substrate

Cordierite is the substrate that posseses a low thermal expansion coefficient, good thermal shock resistance, excellent mechanical properties, and chemical resistance. Thus, cordierite is widely used as substrate for catalysts in high-temperature applications like gaseous treatment. CuMnOx/cordierite catalyst for the complete oxidation of toluene was prepared by the impregnation method and characterized by XRD, BET, IR techniques. This work evaluated the catalytic activity of the prepared catalyst at the temperature range from 150oC to 350oC. It was found that CuMnOx/cordierite catalyst completely converted toluene to CO2 at 350oC. In addition, the mechanism of the toluene oxidation process using CuMnOx/cordierite catalyst was also determined via the indentification of the presentation of the by-products by GC/MS technique at various reaction temperature of 200oC, 250oC, and 350oC. The results showed that the reaction  over the CuMnOx/cordierite catalyst followed the same mechanism as proposed by Lars and Andersson.  The intermediate products of the oxidation process at 200oC, 250oC, and 350oC were benzyl alcohol, benzaldehyde, benzoic acid, benzene, phenol, 1.4-hydroquinone, 1,4- benzoquinone, and maleic anhydride.