Patent ID: 11866387
Assignee: RÖHM GMBH
Field: Organic fine chemistry (Chemistry)
Classification: CPC C  B | IPC B  C

Claim 0:
1. A process for producing methacrylic acid or a methacrylic acid ester, comprising:
a) producing acrolein from a raw material comprising glycerol, wherein the raw material is evaporated and thereafter converted in the presence of a heterogeneous catalyst and a co-feed gas comprising at least one of the components selected from the group consisting of hydrogen, oxygen, and water,
b) reacting the acrolein of process step a) with hydrogen to produce propanal,
c) reacting the propanal of process step b) with formaldehyde to produce methacrolein, and
d) oxidizing the methacrolein in the presence of an oxygen containing gas to the methacrylic acid or in the presence of an alcohol to the methacrylic acid ester,
wherein process step d) is carried out in a liquid phase at a pressure of from 1 to 100 bar, and in the presence of a heterogeneous noble-metal-comprising catalyst comprising a metal and/or a metal oxide, and
wherein the propanal produced in process step b) before being condensed in the presence of formaldehyde in process step c), is purified from hydroxyl acetone.