Process for making propene oxide

US11873285B2 · kind B2 · utility

Assignees

• Evonik Operations GmbH · DE
• thyssenkrupp Uhde GmbH · DE

Inventors

• Maik Bernhard · Bärnsdorf, DE
• Juliette Halli · Frankfurt am Main, DE
• Marc Brendel · Bruchköbel, DE
• Sören Götz · Kahl am Main, DE
• Hans-Christian Dietz · Hattersheim, DE

Key dates

• Filing date: Oct 12, 2022
• Grant date: Jan 16, 2024
• Expiry date: Oct 12, 2042

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/52
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for making propene oxide involves reacting propene with hydrogen peroxide in the presence of methanol, a titanium zeolite epoxidation catalyst, and nitrogen containing compounds present in an amount of from 100 to 3000 mg/kg of hydrogen peroxide. Non-reacted propene is separated from the reaction mixture; the propene depleted reaction mixture is continuously distilled in a distillation column providing an overhead product stream containing propene oxide and methanol and a bottoms product stream; and propene oxide is separated from the overhead product stream. An acid is added to the propane depleted reaction mixture and/or to the distillation column at the same level or above the feed point for the propene depleted reaction mixture and/or contacted to the feed to the distillation column to provide an apparent pH in the bottoms product stream of from 3 to 4.5, which reduces the nitrogen content of the separated propene oxide.