| abstract |
An activated porous phosphorus/vanadium oxide catalyst adapted for the catalytic oxidation of a hydrocarbon to produce a carboxylic acid anhydride. The catalyst comprises a shaped body having a volume of at least about 0.02 cc, a phosphorus content of between about 1.05 and about 1.20, a B.E.T. surface area of at least about 15 m2/g, an average vanadium oxidation state of between about 4.06 and about 4.3, a total pore volume of at least about 0.15 cc/g, a normalized apparent shaped body density of between about 1.0 and about 2.0 g/cc, and a crush strength of at least about 4 pounds. At least about 20% of the pore volume of the catalyst is constituted of pores having a diameter between about 0.1 and about 3.3 mu M, and at least about 40% of the pore volume is constituted of pores having a diameter of less than about 0.1 mu M. The catalyst is prepared by mixing a particulate phosphorus/vanadium oxide precursor with a pore modification agent to produce a modified catalyst precursor composition, forming the modified precursor composition into a predetermined shape, and removing the pore modification agent substantially at a temperature below 300 DEG C., preferably using air as a stripping gas. |