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:
Dec. 02, 2025
Filed:
Oct. 07, 2021
Evonik Operations Gmbh, Essen, DE;
Evonik Operations GmbH, Essen, DE;
Abstract
1,2-propanediol is prepared by a method involving reacting propene with hydrogen peroxide at 50 to 110° C. in the presence of a catalyst mixture, containing a phase transfer catalyst and a polytungstophosphate, in a liquid reaction mixture containing an aqueous phase with a maximum apparent pH of 6 and an organic phase. The method then involves separating the reaction mixture into an aqueous phase containing 1,2-propanediol and an organic phase; recycling at least part of the separated organic phase to the reaction; and recovering 1,2 propanediol from the aqueous phase. The method further involves reacting a tungstate with hydrogen peroxide and phosphoric acid at 5 to 40° C., in the presence of the phase transfer catalyst, in a liquid mixture containing an aqueous and an organic phase, followed by passing at least a part of the resulting organic phase containing the polytungstophosphate and phase transfer catalyst to the initial reaction.