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:
Apr. 28, 2026
Filed:
Oct. 07, 2021
Evonik Operations Gmbh, Essen, DE;
Holger Wiederhold, Darmstadt, DE;
David Bolz, Frankfurt, DE;
Georg Friedrich Thiele, Friedberg, DE;
Bernd Jaeger, Bickenbach, DE;
Hans-Jürgen Köhle, Mainhausen, DE;
Sebastian Imm, Bad Vilbel, DE;
Marina Lazar, Hasselroth, DE;
Evonik Operations GmbH, Essen, DE;
Abstract
A method for preparing 1,2-propanediol involves reacting propene with hydrogen peroxide, in the presence of 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 containing a solvent having a solubility in water at 20° C. of less than 500 mg/kg. The method then involves separating the liquid reaction mixture into an aqueous phase containing 1,2-propanediol and an organic phase; recycling at least a part of the separated organic phase to the reaction; and extracting the separated aqueous phase with an extractant solution containing the same phase transfer catalyst and solvent as used in the reaction to provide an extracted aqueous phase and an extract phase. The method further involves recycling at least a part of the extract phase to the reaction and recovering 1,2-propanediol from the extracted aqueous phase.