Лако-красочные материалы — производство

Phthalic Anhydride from Naphthalene by Catalytic Oxidation54

The heat of combustion of naphthalene is +1234 kilocalories per mole, and of phthalic anhydride, +450 kilocalories per mole.

The catalytic oxidation of naphthalene can easily be carried out in the laboratory, although the amount of phthalic anhydride which can be prepared in one operation is insignificant. It is of great importance that the correct temperature be maintained and that a suitable catalyst be used. Special attention must be given to the apparatus if the prepara­tion in the laboratory is to succeed. Furthermore, it is highly desirable to use a Cottrel precipitator to collect the reaction product completely. This apparatus will collect even the fine particles, which otherwise would be lost.