Process for the preparation of p-benzoquinone

• US 4,973,720 A
• Filed: 10/04/1988
• Issued: 11/27/1990
• Est. Priority Date: 10/16/1987
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Sanko Kaihatsu Kagaku Kenkyusho
• Original Assignee: Sanko Kaihatsu Kagaku Kenkyusho
• Inventors: Ikemoto, Kenichi, Sakaguchi, Katsuya, Saito, Toranosuke, Tsunomachi, Hiroki
• Primary Examiner(s): Garner, Vivian
• Application Number:
  US07/253,056
• Time in Patent Office: 784 Days
• Field of Search: 260/396 R, 552/293
• US Class Current: 552/293
• CPC Class Codes: C07C 46/06 of at least one hydroxy group on a six-membered aromatic ring
• CPC Class Codes: C07C 50/04 Benzoquinones, i.e. C6H4O2

Abstract

There is provided a process of producing p-benzoquinone, wherein hydroquinone and hydrogen peroxide are reacted in water, an aqueous inorganic acid solution, an inert organic polar solvent or a mixture of water with an inert organic polar solvent in the presence of a catalyst selected from the group consisting of iodine, hydrogen iodide, and iodine compounds of metals.

According to the process, p-benzoquinone can be obtained from hydroquinone with the yield and the quality of the p-benzoquinone being high without requiring any special facilities, equipments and operations.

Claims

1. A process of producing p-benzoquinone, wherein hydroquinone and hydrogen peroxide are reacted in water, an aqueous inorganic acid solution, an inert organic polar solvent or a mixture of water with an inert organic polar solvent in the presence of a catalyst selected from the group consisting of iodine, hydrogen iodide, sodium iodide, potassium iodide, lithium iodide, zinc iodide, magnesium iodide, and iodates of alkali metals.

2. A process as claimed in claim 1, wherein said iodine catalyst is used in an amount of 0.01 to 20 wt. % based on the hydroquinone.

3. A process as claimed in claim 1, wherein said hydrogen peroxide is an aqueous hydrogen peroxide solution having a concentration of 20 to 70% by weight.

4. A process as claimed in claim 1, wherein the molar ratio of said hydrogen peroxide to hydroquinone is from 0.8 to 2.0.

5. A process as claimed in claim 1, wherein said inert organic polar solvent is a member selected from the group consisting of methyl alcohol, ethyl alcohol, isopropyl alcohol, and ethylene glycol.