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:
Jun. 30, 2026
Filed:
Oct. 07, 2021
Evonik Operations Gmbh, Essen, DE;
Holger Wiederhold, Darmstadt, DE;
David Bolz, Frankfurt, DE;
Evonik Operations GmbH, Essen, DE;
Abstract
A method for preparing 1,2-propanediol and dipropylene glycol involves continuously reacting propene with hydrogen peroxide in the presence of a catalyst mixture, containing a phase transfer catalyst and a heteropolytungstate, in a liquid reaction mixture containing an aqueous phase with a maximum apparent pH of 6 and an organic phase, to obtain 1,2-propanediol and dipropylene glycol. The method then involves separating the reaction mixture into an aqueous phase (P) containing 1,2-propanediol and dipropylene glycol and an organic phase (P); recycling at least part of the separated organic phase (P) to the reaction; and recovering 1,2-propanediol and dipropylene glycol from the separated aqueous phase (P). The reaction heat generated is at least partially removed, and the ratio of 1,2 propanediol to dipropylene glycol is controlled by adjusting the weight ratio of hydrogen peroxide to water fed to the reaction.