| 摘要 |
1,179,485. Phthalic anhydride. CHEMIEBAU DR. A. ZIEREN G.m.b.H. & CO. K.G. 18 April, 1967 [19 April; 1966], No. 17760/67. Heading C2C. In a process for the manufacture of phthalic anhydride by oxidation of an aromatic hydrocarbon where a gas mixture of air and the aromatic hydrocarbon is passed through a multistage, tray type catalysis apparatus provided with a vanadium oxide catalyst, the temperature of the mixture being adjusted to a predetermined level prior to entry into each tray of the said apparatus when necessary by cooling by indirect heat exchange a mixture derived from a previous tray and the process is so conducted that in a first part of the apparatus including a plurality of trays, in which part the oxidation reaction takes place to the extent of approximately 50%, the temperature is allowed to rise by 50‹ to 60‹ C. in each tray and that in the remainder of the apparatus, also including a plurality of trays, the temperature is allowed to rise by less than 50‹ C. in each tray. O-Xylene and naphthalene are specified starting materials. |
