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:
May. 28, 2019
Filed:
Sep. 14, 2016
Evonik Roehm Gmbh, Darmstadt, DE;
Matthias Groemping, Darmstadt, DE;
Steffen Krill, Muehltal, DE;
Alexander Lygin, Griesheim, DE;
Milica Lukic, Frankfurt, DE;
Steffen Finger, Mainz-Kastel, DE;
Evonik Röhm GmbH, Darmstadt, DE;
Abstract
The present invention relates to a process for preparing methyl methacrylate by direct oxidative esterification of methacrolein. Methyl methacrylate is used in large amounts for preparing polymers and copolymers with other polymerizable compounds. In addition, methyl methacrylate is an important synthesis unit for a variety of specialty esters based on methacrylic acid (MAA) which can be prepared by transesterification with the appropriate alcohol. There is consequently a great interest in very simple, economic and environmentally friendly processes for preparing this starting material. In particular the present invention relates to an optimized workup of the reactor effluent from the oxidative esterification of methacrolein by means of which process waste streams can be minimized and process water can be recycled in optimal fashion. The methacrylic acid generated in the process is also optimally recovered and isolated or converted into the commodity alkyl methacrylate. This process moreover has the advantage that fewer demands than described in the prior art are placed on plant apparatus configuration.