Process for the depolymerization of a furandicarboxylate containing polyester
A product including a furandicarboxylate compound and diol is obtained from a furandicarboxylate containing polyester in a process, which includes reacting a polymer composition including furandicarboxylate containing polyester with water or an alcohol, such as an alkyl alcohol with from 1 to 12 carbon atoms, in the presence of a base, that is preferably selected from the group consisting of metal hydrides, metal alkoxides, metal carbonates, metal carboxylates, N-heterocyclic carbenes, amidines, guanidines, phosphazenes and mixtures thereof.
1. A process for the depolymerization of a furandicarboxylate containing polyester, which process comprises reacting the polyester with an alcohol or water in the presence of a depolymerisation catalyst to yield a product comprising a furandicarboxylate compound and diol.
2. The process according to claim 1 , wherein the polyester comprises poly(alkylene 2,5-furandicarboxylate).
3. The process according to claim 2 , wherein the alkylene moiety of the poly(alkylene 2,5-furandicarboxylate) comprises 2 to 6 carbon atoms.
4. The process according to claim 1 , wherein the depolymerisation catalyst comprises an acid catalyst, a metal compound or a base.
5. The process according to claim 4 , wherein the depolymerisation catalyst comprises a base.
6. The process according to claim 5 , wherein the base is selected from the group consisting of metal alkoxides, metal hydroxides, metal carbonates, metal carboxylates, N-heterocyclic carbenes, amidines, guanidines, phosphazenes and mixtures thereof.
7. The process according to claim 1 , which is preceded by dispersing at least part of the polyester in an alcohol or water to yield a polyester slurry.
8. The process according to claim 1 , when water and a base are used, free dicarboxylic acid is obtained after treatment with a Brønsted acid.
9. The process according to claim 1 , wherein the furandicarboxylate containing polyester is part of a polymer composition further comprising one or more polymers selected from the group consisting of polyethyleneterephthalate, polyolefins, polyvinylchloride, polylactic acid, polyamides and mixtures thereof.
10. The process according to claim 9 , wherein the polymer composition has been obtained from waste.
11. The process according to claim 1 , wherein the alcohol comprises from 1 to 12 carbon atoms, the alcohol preferably being methanol, ethanol, ethylene glycol, 1,3-propane diol, 1,4-butadiol or a mixture thereof.
12. The process according to claim 1 , wherein the reaction temperature ranges from room temperature to 350° C.
13. The process according to claim 1 , wherein the process is performed in batch mode.
14. The process according to claim 1 , wherein a stream containing the polymer composition is continuously fed into a reactor and a product stream containing furandicarboxylate compound and diol is continuously withdrawn from the reactor.
15. The process according to claim 14 , wherein the process is conducted in a continuous stirred tank reactor.
16. The process according to claim 14 , wherein furandicarboxylate compound is separated from the product stream.
17. The process according to claim 16 , wherein at least part of the furandicarboxylate compound that has been separated from the product stream is used for the manufacture of poly(alkylene furandicarboxylate).