Combustion of phthalic anhydride over V[subscript 2]O[subscript 5]/TiO[subscript 2] catalysts promoted with transition metal and MgO

Abstract

The oxidation property of V[subscript 2]O[subscript 5]/TiO[subscript 2] catalyst unpromoted and promoted with transition metal (Fe, Cu, Zn and Mo) and magnesium oxide on the combustion of phthalic anhydride was investigated. The result showed that the V[subscript 2]O[subscript 5]/TiO[subscript 2] catalyst was not active for the combustion of phthalic anhydride. After adding both transition metal and magnesium oxide to the V[subscript 2]O[subscript 5]/TiO[subscript 2] catalyst, it was found that metal-V-Mg-O/TiO[subscript 2] catalysts showed the phthalic anhydride combustion activity higher than the unpromoted V[subscript 2]O[subscript 5]/TiO[subscript 2] catalyst, indicating that the added transition metal and magnesium were able to catalyze the reaction. This is due to the addition of metal oxide to V[subscript 2]O[subscript 5]/TiO[subscript 2] catalyst would increase the active sites on the surface of catalysts. Moreover, the addition of magnesium oxide would increase the numbers of the basic sites on surface of V[subscript 2]O[subscript 5]/TiO[subscript 2] catalyst and increased the adsorption of phthalic anhydride, thus, provided more opportunity to react with metal.