Patent ID: 7038065

Claim:
A process for catalytically generating phthalic anhydride, maleic anhydride, acetic acid or acrylic acid by partial oxidation of butane, benzene, propylene, naphthalene, C 4 hydrocarbons, or anthraguinone in the presence of molecular oxygen at temperatures in the range from 200 to 500° C. in one reactor or a plurality of series-connected reactors containing a catalyst for generating a gaseous product mixture, wherein at least one reactor is a cooling-tube reactor with cooling tubes through which flows a cooling fluid, wherein the cooling-tube reactor 40 to 100 wt-% of the total amount of the catalyst is disposed as a coating on the outside of the cooling tubes and the feed mixture containing the feedstock and the molecular oxygen is brought into contact with the catalyst coating, and a plurality of cooling systems are provided, which deliver cooling fluid to the cooling tubes of the cooling-tube reactor and withdraw the same therefrom.