	US 11,905,239 B2
	Process for producing methacrylic acid or methacrylic acid esters
Alexander May, Seeheim-Jugenheim (DE); Steffen Krill, Muehltal (DE); Marcel Treskow, Mobile, AL (US); Diego Carambia, Jose C. Paz (AR); and Gabriel Avella, San Isidro (AR)
Assigned to Röhm GmbH, Darmstadt (DE)
Filed by Röhm GmbH, Darmstadt (DE)
Filed on Nov. 17, 2022, as Appl. No. 18/056,338.
Application 18/056,338 is a division of application No. 17/266,735, previously published as PCT/EP2019/068644, filed on Jul. 11, 2019.
Claims priority of application No. 18188458 (EP), filed on Aug. 10, 2018.
Prior Publication US 2023/0080750 A1, Mar. 16, 2023
Int. Cl. C07C 67/39 (2006.01); B01J 23/38 (2006.01); B01J 35/02 (2006.01); C07C 45/75 (2006.01); C07C 45/83 (2006.01); C07C 51/25 (2006.01); B82Y 30/00 (2011.01); B82Y 40/00 (2011.01)

CPC C07C 67/39 (2013.01) [B01J 23/38 (2013.01); B01J 35/023 (2013.01); C07C 45/75 (2013.01); C07C 45/83 (2013.01); C07C 51/252 (2013.01); B82Y 30/00 (2013.01); B82Y 40/00 (2013.01)]

19 Claims

1. A process for producing methacrylic acid or a methacrylic acid ester, the process comprising:

a) producing acrolein from a raw material comprising propylene,

b) reacting the acrolein of a) with hydrogen to produce propanal,

c) reacting the propanal of b) with formaldehyde to produce methacrolein,

d) oxidizing the methacrolein in the presence of an oxygen containing gas and optionally an alcohol, to the methacrylic acid or the methacrylic acid ester, and

wherein the acrolein of a) is hydrogenated in the presence of acrylic acid, which is formed in a) as a byproduct, and wherein the acrylic acid is hydrogenated to propionic acid in b).