Process for the production of dialkyl terephthalate

Patent metadata

Field	Value
Publication number	US-2021122698-A1
Application number	US-201916981964-A
Country	US
Kind code	A1
Filing date	Mar 28, 2019
Priority date	Apr 18, 2018
Publication date	Apr 29, 2021
Grant date	—

Abstract

A process for preparing dialkyl terephalate comprising the following steps:—i) providing furan-2,5-dicarboxylate; ii) esterifying the furan-2,5-dicarboxylate with alcohol to form furan-2,5-carboxylic acid dialkyl ester; iii) reacting the furan-2,5-carboxylic acid dialkyl ester with ethylene under Diels Alder conditions, elevated temperature and pressure and in the presence of a catalyst such that dialkyl terephthalate is produced; wherein the Diels-Alder reaction is free from solvent; wherein the catalyst comprises a clay comprising metal ions and having Lewis acidity.

First claim

1 . A process for preparing dialkyl terephalate comprising:
esterifying furan-2,5-dicarboxylate with an alcohol to form furan-2,5-carboxylic acid dialkyl ester; and reacting the furan-2,5-carboxylic acid dialkyl ester with ethylene under Diels Alder conditions, elevated temperature and pressure and in the presence of a catalyst such that dialkyl terephthalate is produced;
wherein the Diels-Alder reaction is free from solvent; and
wherein the catalyst comprises a clay comprising metal ions and having Lewis acidity.

2 . The process as claimed in claim 1 further comprising converting the dialkyl terephthalate into a product selected from the group consisting of a) terephthalate polyesters, b) poly(butyleneterphalate-co-butyleneadipate and c) terephthalate plasticizers, which are terephthalate diesters where the alkyl groups are longer carbon chains selected from straight and branched.

3 . The process as claimed in claim 1 , wherein the dialkyl terephthalate is diethyl terephthalate.

4 . The process as claimed in claim 2 , comprising converting the dialkyl terephthalate into polyalkylene terephthalate.

5 . The process as claimed in claim 1 , wherein the alcohol is a bioalcohol.

6 . The process as claimed in claim 1 , wherein the alcohol is selected from an aliphatic alcohol, a benzyl alcohol and a phenolic alcohol.

7 . The process as claimed in claim 1 , wherein the alcohol is selected from the group consisting of bio-methanol, bio-ethanol, bio-propanol, and mixtures thereof.

8 . The process as claimed in claim 1 , wherein an intermediate is formed during the Diels-Alder reaction, which is a bi-cyclic oxo-adduct.

9 . The process as claimed in claim 1 , wherein the Diels-Alder reaction is carried out in a solvent free environment.

10 . The process as claimed in claim 1 , wherein the clay is a smectite clay selected from the classes of the montmorillonites, hectorites, volchonskoites, nontronites, saponites, beidelites and sauconites.

11 . The process as claimed in claim 1 , wherein the catalyst is selected from cation-exchanged clays and pillared clays.

12 . The process as claimed in claim 11 , wherein the cation is selected from the group consisting of aluminium, zirconium, titanium and copper.

13 . The process as claimed in claim 11 , wherein the pillared clay is selected from the group consisting of aluminium pillared clay, zirconium pillared clay, titanium pillared clay and copper pillared clay.

14 . The process as claimed in claim 1 , wherein the furan-2,5-carboxylic acid dialkyl ester is pre-adsorbed onto the clay catalyst.

15 . The process as claimed in claim 1 , which is a batch process.

16 . The process as claimed in claim 2 , comprising converting the dialkyl terephthalate into polyethylene terephthalate.

17 . The process as claimed in claim 7 , wherein the alcohol is bio-ethanol.

18 . The process as claimed in claim 10 , wherein the clay is a montmorillonite clay.

19 . The process as claimed in claim 11 , wherein the catalyst is pillared clays.

20 . The process as claimed in claim 12 , wherein the cation is aluminium.

21 . The process as claimed in claim 13 , wherein the pillared clay is aluminium pillared clay.

Assignees

• Conopco Inc Dba Unilever

Inventors

• Breeden Simon William
• Clark James Hanley
• Farmer Thomas James
• Macquarrie Duncan James
• Mcelroy Con Robert
• Ogunjobi Joseph Kolawole
• Thornthwaite David William

Classifications

• C07C69/82

  Terephthalic acid esters · CPC title

• B01J37/30

  Ion-exchange · CPC title

• C07C67/347 Primary

  by addition to unsaturated carbon-to-carbon bonds · CPC title

• B01J21/16

  Clays or other mineral silicates · CPC title