US 12,258,669 B2
Process and system for the electrochemical reduction of oxalic acid
Arnaud Mol, Amsterdam (NL); Faezeh Esmaeili, Amsterdam (NL); Matthew Philips, Amsterdam (NL); and Mariana Paredinha Araujo, Amsterdam (NL)
Assigned to Avantium Knowledge Centre B.V., Amsterdam (NL)
Appl. No. 18/037,435
Filed by Avantium Knowledge Centre B.V., Amsterdam (NL)
PCT Filed Nov. 25, 2021, PCT No. PCT/EP2021/082909
§ 371(c)(1), (2) Date May 17, 2023,
PCT Pub. No. WO2022/112375, PCT Pub. Date Jun. 2, 2022.
Claims priority of application No. 20210026 (EP), filed on Nov. 26, 2020.
Prior Publication US 2023/0416930 A1, Dec. 28, 2023
Int. Cl. C25B 3/25 (2021.01); C25B 3/07 (2021.01); C25B 9/13 (2021.01); C25B 9/19 (2021.01); C25B 15/02 (2021.01); C25B 15/023 (2021.01); C25B 15/029 (2021.01); C25B 15/08 (2006.01)
CPC C25B 3/07 (2021.01) [C25B 3/25 (2021.01); C25B 9/13 (2021.01); C25B 15/023 (2021.01); C25B 15/087 (2021.01)] 10 Claims
OG exemplary drawing
 
1. A process for the electrochemical reduction of oxalic acid to glyoxylic acid, wherein the process is performed in an electrochemical cell comprising a cathode compartment containing a cathode, an anode compartment containing an anode, and an ion exchange membrane separating the anode compartment from the cathode compartment, wherein the process comprises the steps of:
(a) feeding an anolyte comprising an acid to the anode compartment;
(b) feeding a liquid catholyte comprising an aqueous oxalic acid solution to the cathode compartment, wherein the liquid catholyte is moving in a catholyte loop by being passed from a catholyte holding tank into the cathode compartment, over the surface of the cathode, being removed from the cathode compartment as an oxalic acid-depleted catholyte and returned to the catholyte holding tank;
(c) applying an electric potential difference between the cathode and the anode sufficient to produce a glyoxylic acid recoverable from the cathode compartment,
wherein during the process one or more quantities of concentrated oxalic acid solution are provided to the liquid catholyte by the steps of:
(d) withdrawing a portion of the oxalic acid-depleted catholyte and contacting it with a quantity of solid oxalic acid to provide a concentrated oxalic acid solution; and
(e) feeding at least a portion of the concentrated oxalic acid solution to the catholyte holding tank.