The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 01, 1999
Filed:
Mar. 25, 1997
Kazuharu Ogasawara, Kamisu-machi, Kashima-gun, Ibaraki-ken, JP;
Tomio Kato, , US;
Kazuyuki Minato, , US;
Kenji Kato, , US;
Makoto Sumitani, , US;
Abstract
A regeneration method of a working solution is herein disclosed in which various by-products which do not participate in the production of hydrogen peroxide and which are present in the working solution in a hydrogen peroxide production process utilizing an anthraquinone method can efficiently be converted into anthraquinones effective as reaction media for the production of hydrogen peroxide. The present invention is concerned with (1) a regeneration method of a working solution wherein at least a part of the unreduced working solution is brought into contact with a catalyst mainly comprising a .gamma.-alumina at a temperature of 40 to 150.degree. C., and (2) another regeneration method of a working solution wherein the working solution is brought into contact with a catalyst mainly comprising a .gamma.-alumina at a temperature of 20 to 150.degree. C. under conditions that a concentration h (mol/liter) of the alkyltetrahydroanthrahydroquinones in the working solution before the catalytic treatment meets the equation