Abstract: Catalytic compositions of oxides of titanium, vanadium and tin that are suitable for the production of phthalic anhydride by oxidizing o-xylene and/or naphthalene in the gas phase. The catalysts exhibit excellent activity and selectivity. The catalyst contains 2 to 15 percent by weight (calculated as V2O5) of vanadium, 1 to 15 percent weight (calculated as SnO2) of tin and 70 to 97 percent by weight (calculated as TiO2) of titanium. In a preferred embodiment the catalyst also contains up to 5 percent by weight (calculated as M2O) of at least one alkali metal, preferably lithium, potassium or rubidium, and more preferably cesium. In an even more preferred embodiment, cesium is present in an amount of from 0.01 to 2 percent by weight (calculated as Cs2O).

Abstract: Disclosed are catalytic compositions comprising oxides of titanium vanadium and tin which are suitable for the production of phthalic anhydride by oxidizing o-xylene and/or napthalene in the gas phase. The catalysts exibit excellent activity and selectivity. The catalyst comprise 2 to 15% by weight (calculated as V2O5) of vanadium, from 1 to 15% by weight (calculated as SnO2) of tin and further comprise from 70 to 97% by weight (calculated as TiO2) of titanium. In a preferred embodiment the catalyst of the invention comprise up to 5% by weight (calculated as M2O) of at least tine alkali metal preferably lithium, potassium or rubidium, and more preferably cesium. In an even more preferred embodiment, cesium is present in an amount of from 0.01 to 2% by weight (calculated as Cs2O).