Method for the preparation of 2,5-furandicarboxylic acid and esters thereof
A method for the preparation of 2,5-furandicarboxylic acid (“FDCA”) and/or an alkyl ester of FDCA includes the step of contacting a feed comprising a starting material selected from 5-alkoxymethylfurfural, 2,5-di(alkoxymethyl)furan and a mixture thereof with an oxidant in the presence of an oxidation catalyst. The feed may also comprise 5-hydroxymethylfurfural as a further starting material.
1. A method for the preparation of 2,5-furandicarboxylic acid and/or an alkyl ester of 2,5-furandicarboxylic acid comprising the step of contacting a feed comprising a starting material selected from 5-alkoxymethylfurfural, 2,5-di(alkoxymethyl)furan and a mixture thereof wherein the alkyl group is methyl or ethyl, with an oxidant in the presence of an oxidation catalyst.
2. The method according to claim 1 , wherein the feed comprises 5-hydroxymethylfurfural as a further starting material.
3. The method according to claim 1 , wherein the oxidation catalyst comprises at least one metal selected from the group consisting of Co and Mn.
4. The method according to claim 1 , wherein the oxidation catalyst comprises a source of bromine.
5. The method according to claim 3 , wherein the oxidation catalyst contains both Co and Mn.
6. The method according to claim 5 , wherein the oxidation catalyst comprises at least one additional metal.
7. The method according to claim 6 , wherein the additional metal is Zr, Ce or a mixture thereof.
8. The method according to claim 1 , wherein the oxidant is selected from oxygen, air or other oxygen-containing gases.
9. The method according to claim 1 , wherein the feed and the oxidant are contacted at a temperature between 60 and 220° C.
10. The method according to claim 1 , wherein a solvent or solvent mixture is present.
11. A method for the preparation of a dialkylester of 2,5-furandicarboxylic acid, comprising preparing 2,5-furandicarboxylic acid or an alkyl ester of 2,5-furandicarboxylic acid in a method comprising the step of contacting a feed comprising a starting material selected from 5-alkoxymethylfurfural, 2,5-di(alkoxymethyl)furan and a mixture thereof, with an oxidant in the presence of an oxidation catalyst, to obtain a reaction product, and reacting the reaction product with a C 1 -C 5 alkyl alcohol to obtain the dialkyl ester of 2,5-furandicarboxylic acid.
12. The method according to claim 11 , wherein the C 1 -C 5 alkylalcohol is methanol and the dialkyl ester is the dimethylester of 2,5-furan dicarboxylic acid.
13. The method according to claim 9 , wherein the feed and the oxidant are contacted at a temperature, between 100 and 210° C.
14. The method according to claim 9 , wherein the feed and the oxidant are contacted at a temperature between 150 and 200° C.
15. The method according to claim 9 , wherein the feed and the oxidant are contacted at a temperature between 160 and 190° C.
16. The method according to claim 10 , wherein the solvent contains a monocarboxylic acid functional group.
17. The method according to claim 10 , wherein the solvent contains acetic acid or a mixture of acetic acid and water.