US 12,466,934 B2
Method for recycling polyester fabrics with use of ionic liquid catalyst
Te-Chao Liao, Taipei (TW); Jung-Jen Chuang, Taipei (TW); Wei-Sheng Cheng, Taipei (TW); Zhang-Jian Huang, Taipei (TW); and Yu-Ti Tseng, Taipei (TW)
Assigned to NAN YA PLASTICS CORPORATION, Taipei (TW)
Filed by NAN YA PLASTICS CORPORATION, Taipei (TW)
Filed on Jun. 26, 2022, as Appl. No. 17/849,691.
Claims priority of application No. 110131554 (TW), filed on Aug. 26, 2021.
Prior Publication US 2023/0062055 A1, Mar. 2, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. C08J 11/28 (2006.01); B01D 15/16 (2006.01); B01D 15/36 (2006.01); B01D 17/02 (2006.01); B01J 31/02 (2006.01); B09B 3/70 (2022.01); B29B 17/00 (2006.01); B09B 101/75 (2022.01); B09B 101/85 (2022.01); B29K 67/00 (2006.01)
CPC C08J 11/28 (2013.01) [B01D 15/161 (2013.01); B01D 15/361 (2013.01); B01D 17/0208 (2013.01); B01J 31/0284 (2013.01); B01J 31/0295 (2013.01); B09B 3/70 (2022.01); B29B 17/00 (2013.01); B09B 2101/75 (2022.01); B09B 2101/85 (2022.01); B29K 2067/003 (2013.01); C08J 2367/02 (2013.01)] 8 Claims
 
1. A method for recycling polyester fabrics with use of an ionic liquid catalyst, comprising:
implementing a preparation operation, which includes providing a recycled polyester fabric;
implementing a de-polymerization operation, which includes using a chemical de-polymerization liquid to chemically de-polymerize the recycled polyester fabric and form a de-polymerization product, wherein the de-polymerization product includes bis-2-hydroxylethyl terephthalate (BHET); wherein the de-polymerization operation is to chemically de-polymerize the recycled polyester fabric in an environment where the ionic liquid catalyst is present; wherein the ionic liquid catalyst includes a substrate and ionic liquids grafted onto the substrate, the substrate is made of carbon, silicon, iron, nickel, and/or cobalt, and an average particle size of the substrate is between 2 micrometers and 800 micrometers; and
implementing a separation operation, which includes separating the ionic liquid catalyst from the de-polymerization product by one or both of a centrifugal method and a filtering method, so as to collect and recycle the ionic liquid catalyst for use.