Process for the production of glycolic acid

Patent metadata

Field	Value
Publication number	US-2025109088-A1
Application number	US-202318834488-A
Country	US
Kind code	A1
Filing date	Mar 14, 2023
Priority date	Mar 15, 2022
Publication date	Apr 3, 2025
Grant date	—

Abstract

A process for the production of glycolic acid may include subjecting an aqueous oxalic acid solution to a hydrogenation reaction in the presence of hydrogen and a metal containing hydrogenation catalyst. The process may bea continuous flow process in a fixed bed reactor andthe aqueous oxalic acid solution and a hydrogen gas stream are fed to the fixed bed reactor, the aqueous oxalic acid solution in the feed having an oxalic acid concentration up to 100% saturation at the feed temperature.The reactor may include a hydrogenation catalyst bed, the catalyst being a supported metal containing hydrogenation catalyst andthe hydrogenation reaction is performed at a temperature selected from the range of from equal to and higher than 40° C. up to equal to and lower than 85° C., at a hydrogen pressure selected from the range of from equal to and higher than 10 bar H2 up to equal to and lower than 150 bar H2.

First claim

1 . A process for the production of glycolic acid comprising subjecting an aqueous oxalic acid solution to a hydrogenation reaction in the presence of hydrogen and a metal containing hydrogenation catalyst,
wherein the process is a continuous flow process in a fixed bed reactor; and wherein the aqueous oxalic acid solution is potassium free; and wherein the aqueous oxalic acid solution and a hydrogen gas stream are fed to the fixed bed reactor, the aqueous oxalic acid solution in the feed having an oxalic acid concentration up to 100% saturation at the feed temperature; and wherein the reactor comprises a hydrogenation catalyst bed, the catalyst being a supported metal containing hydrogenation catalyst with a total metal loading of from equal to and higher than 2.0 wt % up to equal to and lower than 20.0 wt %; and wherein the hydrogenation reaction is performed at a temperature selected from the range of from equal to and higher than 40° C. up to equal to and lower than 85° C., at a hydrogen pressure selected from the range of from equal to and higher than 10 bar H 2 up to equal to and lower than 150 bar H 2 , at a residence time of equal to or longer than 5 minutes up to equal to or less than 1 hour; to produce glycolic acid with high selectivity of 80% and higher, at a conversion of oxalic acid of 80% to 100%.

2 . The process of claim 1 , wherein the reactor is a trickle bed reactor.

3 . The process of claim 1 , wherein the hydrogenation catalyst contains one or more metals selected from group A metals: platinum, nickel, copper, ruthenium, rhodium and iridium, and optionally one other metal selected from group B metals: tin, bismuth, palladium, rhenium, gold, and antimony.

4 . The process of claim 1 , wherein the hydrogenation catalyst contains ruthenium as group A metal.

5 . The process of claim 4 , wherein the hydrogenation catalyst contains ruthenium and tin.

6 . The process of claim 5 , wherein the molar ratio of ruthenium to tin in the catalyst is from 10:1 to 1:10.

7 . The process of claim 1 , wherein the catalyst is a trimetallic catalyst containing ruthenium, platinum and tin.

8 . The process of claim 1 , wherein the hydrogenation catalyst is supported on a carrier selected from carbon, silicon carbide, MAX-Phase (Ti 2 Al 2 C), TiO 2 and ZrO 2 .

9 . The process of claim 1 , wherein the hydrogenation reaction is performed in a reactor with non-metallic or inert liners.

Assignees

• Avantium Knowledge Centre Bv

Inventors

• Gruter Gerardus Johannes Maria
• Schuler Eric
• Raveendran Shiju Nirappurackal

Classifications

• B01J23/626

  with tin · CPC title

• C07C51/377 Primary

  by splitting-off hydrogen or functional groups; by hydrogenolysis of functional groups {(C07C51/36 - C07C51/373 take precedence)} · CPC title

• C07C51/367 Primary

  by introduction of functional groups containing oxygen only in singly bound form · CPC title