Separation and purification of hydroquinone from crude mixtures thereof

US8404085B2 · kind B2 · utility

Assignee

• RHODIA OPERATIONS · FR

Inventors

• Hubert Gayet · Villeurbanne, FR
• Bruno Heinisch · Villeurbanne, FR

Key dates

• Filing date: Jun 27, 2007
• Grant date: Mar 26, 2013
• Expiry date: Sep 2, 2029

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C37/685
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Separation and purification of hydroquinone from crude mixtures thereof essentially containing hydroquinone in combination with very small amounts of impurities including resorcinol and pyrogallol, include a topping distillation allowing the resorcinol to be removed as the distillation top product, and allowing a crude mixture essentially containing hydroquinone and the heavy impurities to be recovered at the column bottom, such mixture then being subjected to a bottoming distillation which allows the pyrogallol to be removed at the column bottom and allows hydroquinone in a purified form to be recovered at the column top.