US 12,145,905 B2
Oxidative preparation of maleic acid
Johan Urbanus, 's-Gravenhage (NL); Marc Crockatt, 's-Hertogenbosch (NL); Earl Lawrence Vincent Goetheer, Mol (BE); and Roman Latsuzbaia, Delft (NL)
Assigned to Nederlandse Organisatie voor toegepast-natuurwetenschappelijk onderzoek TNO, 's-Gravenhage (NL)
Appl. No. 17/414,995
Filed by Nederlandse Organisatie voor toegepast-natuurwetenschappelijk onderzoek TNO, 's-Gravenhage (NL)
PCT Filed Dec. 20, 2019, PCT No. PCT/NL2019/050869
§ 371(c)(1), (2) Date Jun. 17, 2021,
PCT Pub. No. WO2020/130834, PCT Pub. Date Jun. 25, 2020.
Application 17/414,995 is a continuation of application No. PCT/NL2018/050881, filed on Dec. 21, 2018.
Prior Publication US 2022/0064097 A1, Mar. 3, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. C07C 51/235 (2006.01); C25B 3/07 (2021.01); C25B 3/23 (2021.01); C25B 11/04 (2021.01); C25B 11/042 (2021.01); C25B 11/052 (2021.01)
CPC C07C 51/235 (2013.01) [C25B 3/07 (2021.01); C25B 3/23 (2021.01); C25B 11/04 (2013.01); C25B 11/042 (2021.01); C25B 11/052 (2021.01)] 16 Claims
 
1. A process for the preparation of maleic acid, or a derivative thereof selected from the group consisting esters of maleic acid, amides of maleic acid, maleimides, anhydrides of maleic acid, and maleic anhydride, said process comprising a first step comprising an electrochemical oxidation in an electrolyte solution of a furanic compound into one or more intermediates; wherein said furanic compound is a compound according to formula I of which R1 is H, CH2OH, CO2H or CHO and R2 is or an ester, ether, amide, acid halide, anhydride, carboximidate, nitrile, or salts of said compound according to formula I;

OG Complex Work Unit Chemistry
a second step which follows the first step and comprises a chemo-catalytic oxidation of said intermediates to provide maleic acid or the derivative thereof, which chemo-catalytic oxidation is a non-electrochemical oxidation.