PURPOSE: In producing the titled substance useful as a raw material for polyimide, etc., by nitric acid oxidation method for aromatic hydrocabon, to reduce an amount of nitric acid used by the use of a by-product and to improve yield, by oxidizing a nitrogen oxide as a by-product with oxygen fed to raise concentration of nitric acid and to promote the oxidation reaction.
CONSTITUTION: An aromatic hydrocarbon [e.g., bis(dimethylphenyl)ethane, etc.] shown by the formula (R1WR6 are H, or 1W3C alkyl, and at least two of R1WR6 are alkyl; R7 are 1W3C alkylene) as a raw material is reacted with nitric acid. The oxidation reaction is carried out in a pressure reactor, and the reaction pressure is 30W100kg/cm2. Then, the reaction is continuously done in the presence of oxygen, to give the aimed compound. The reaction temperature of the secondary oxidation reaction is preferably 160W200°C, the pressure is 30W80kg/cm2, and an amount of oxygen fed is 0.05W5mol, preferable 0.1W2mol based on 1mol aromatic hydrocarbon.
FUJIWARA HIDEETSU
HOSOYA KENJI
