Patent · US Active

Process for preparing unsaturated esters proceeding from aldehydes by direct oxidative esterification

US9617199B2 · kind B2 · utility

25Cited by

1References

18Claims

0Family size

Assignee

Evonik Röhm GmbH · DE

Inventors

Steffen Krill · Mühltal, DE
Alexander Lygin · Griesheim, DE
Torsten Balduf · Pfungstadt, DE
Rudolf Burghardt · Darmstadt, DE
Andreas Tepperis · Bad König, DE
Matthias Groemping · Darmstadt, DE

Key dates

Filing date	Dec 5, 2014
Grant date	Apr 11, 2017
Priority date	—
Expiry date	Dec 5, 2034

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY02P20/582
WIPO fieldChemical engineering
WIPO sectorChemistry

Abstract

The present invention relates to a process for preparing methyl methacrylate by a direct oxidative esterification of methacrolein with oxygen and methanol, which is conducted in the liquid phase at a pressure of 2 to 100 bar with a gold catalyst. According to the invention, the liquid phase is withdrawn continuously from the reactor and optionally enriched with oxygenous gas, the pH, after the withdrawal, is adjusted to a pH between 5 and 9 by means of addition of a basic solution and this liquid phase is conducted back into the reactor again to an extent of at least 50%.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.