Method of making halophthalic acids and halophthalic anhydrides

US7541489B2 · kind B2 · utility

Assignee

• Sabic Innovative Plastics B.V. · NL

Inventors

• Robert Edgar Colborn · Niskayuna, US
• David Bruce Hall · Ballston Lake, US
• Peter Koch · Frankfurt, DE
• Bernd Volker Demuth · Offenbach, DE
• Thomas Wessel · Frankfurt, DE
• KarlErnst Mack · Wiesbaden, DE
• Prashant Tatake · Hyderabad, IN
• Utpal Mahendra Vakil · Mumbai, IN
• Shyamal Bhaskar Gondkar · Savanuru, IN
• John E. Pace · Washington, US
• Kwang Woong Won · San Clemente, US

Key dates

• Filing date: Jun 29, 2005
• Grant date: Jun 2, 2009
• Expiry date: Jan 29, 2026

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C51/265
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A method of preparing a halophthalic acid is disclosed which comprises the steps of contacting in a liquid phase reaction mixture at least one halogen-substituted ortho-xylene with oxygen and acetic acid at a temperature in a range between about 120° C. and about 220° C. in the presence of a catalyst system yielding a product mixture comprising less than 10 percent halogen-substituted ortho-xylene starting material, a halophthalic acid product, and less than about 10,000 ppm halobenzoic acid and less than about 1000 ppm halophthalide by-products based on a total amount of halophthalic acid present in the product mixture. In addition methods for the preparation of halophthalic anhydride, and recovery of high purity acetic acid from an aqueous acetic acid stream comprising HCl, which is generated during the preparation of the halophthalic acid are also disclosed.