Title:
【発明の名称】ナフタレンの気相酸化反応ガスからナフトキノン及び無水フタル酸を単離する方法
Document Type and Number:
Japanese Patent JPS5825650
Kind Code:
B2
Abstract:
To isolate naphthoquinone and phthalic anhydride from the gas obtained in the gas phase oxidation of naphthalene, the gas product at 250 DEG to 500 DEG C is first quenched with a counter-current liquid stream of naphthalene, naphthoquinone and phthalic anhydride. The liquid is raised to at most 200 DEG C, cooled and partly recycled, the coolant temperature being within 70 DEG C of the temperature of the liquid being cooled. The portion of the quench liquid which is not recycled is the product, viz. a solution of naphthoquinone and phthalic anhydride in naphthalene. The quenched gas is scrubbed with liquid naphthalene and most of the liquid product is cooled and re-cycled, the balance of the liquid product being passed to the quencher. The gas which leaves the scrubber is substantially free from naphthoquinone and phthalic anhydride. The initial gas may have been pre-cooled by evaporative cooling. The surfaces of the quencher, cooler and pipes of the quenching system are preferably of stainless steel or are smoothed either mechanically or by coating with plastic, enamel, ceramic or metal.
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Inventors:
YOAHIMU PURIIMAA
NORUBERUTO SHENKU
IERUKU KUREKERU
BURUKU SHUBAATERU
NORUBERUTO SHENKU
IERUKU KUREKERU
BURUKU SHUBAATERU
Application Number:
JP8359976A
Publication Date:
May 28, 1983
Filing Date:
July 15, 1976
Export Citation:
Assignee:
BAYER AG
International Classes:
C07D307/89; C07C45/00; C07C46/10; C07C50/12; C07C50/18; C07C51/573; C07C67/00; (IPC1-7): C07C50/18; C07D307/89
Attorney, Agent or Firm:
Heiyoshi Odashima