Depolymerization of polymers with ester, ether and carbonate linkages using acidic ionic liquid (AIL) catalyst
AssigneeCouncil of Scientific and Industrial Research An Indian Resgistered Body Incorporated Under the Regn. of Soc. Act (Act Xxi of 1860)
InventorsParesh Laxmikant Dhepe, Manuraj Kallumkal
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Abstract
The present invention provides an effective and selective process for the depolymerization of polyethylene terephthalate (PET), polyethylene furanoate (PEF), polylactic acid, polycarbonates, polyethers and polyamides into pure and high yielding valorized products by combining the glycolysis-hydrolysis reactions using a homogeneous acidic ionic liquid (AIL) catalyst, resulting in excellent polymer conversion.
Claims4
A process for the depolymerization of polymers, the process comprising the steps of:
- a) heating a mixture of polymer and an acidic ionic liquid (AIL) catalyst, wherein polymer to catalyst ratio is in the range of 20.0:0.01-20:10.0 (mol/mol), in an ethylene glycol:dioxane solvent mixture, wherein ethylene glycol:dioxane ratio is in the range of 1.0:0.01-1.0:5.0 (v/v), at a temperature in the range of 120-250° C. for a period in the range of 0.5 to 24 hour, whereby a reaction mixture is obtained,
- b) adding water and diethyl ether into the reaction mixture obtained at step a) after completion of the reaction;
- c) washing ether layer obtained at step b) with aqueous NaOH solution;
- and
- d) acidifying the aqueous layer obtained at step c) to afford valorized product with 100% polymer conversion.
Dependencies are inferred from the claim text.