Process for preparing 1,4-naphthoquinone

US4032548A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Manfred Martin
• Gerhard Scharfe · Leverkusen, DE

Key dates

• Filing date: Jul 9, 1975
• Grant date: Jun 28, 1977
• Expiry date: Jul 9, 1995

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S502/514
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

1,4-Naphthoquinone is prepared by reacting naphthalene with molecular oxygen in a gaseous phase in the presence of a catalyst containing vanadium. Prior to reacting the naphthalene with oxygen, the catalyst is pre-treated with molecular oxygen at 300.degree. to 400.degree. C in the absence of organic compounds and immediately thereafter a gas mixture containing naphthalene and molecular oxygen is passed over the pretreated catalyst at temperatures in the range of 300.degree. to 400.degree. C. The catalyst pre-treatment can be carried out in the presence of water vapor and the subsequent reaction of naphthalene with molecular oxygen can also be carried out in the presence of water vapor.