Chemical Recycling of a Textile Blend from Polyester and Viscose, Part II: Mechanism and Reactivity during Alkaline Hydrolysis of Textile Polyester
Journal article, 2022

Chemical recycling of textiles holds the potential to yield materials of equal quality and value as products from virgin feedstock. Selective depolymerization of textile polyester (PET) from regenerated cellulose/PET blends, by means of alkaline hydrolysis, renders the monomers of PET while cellulose remains in fiber form. Here, we present the mechanism and reactivity of textile PET during alkaline hydrolysis. Part I of this article series focuses on the cellulose part and a possible industrialization of such a process. The kinetics and reaction mechanism for alkaline hydrolysis of polyester packaging materials or virgin bulk polyester are well described in the scientific literature; however, information on depolymerization of PET from textiles is sparse. We find that the reaction rate of hydrolysis is not affected by disintegrating the fabric to increase its surface area. We ascribe this to the yarn structure, where texturing and a low density assures a high accessibility even without disintegration. The reaction, similar to bulk polyester, is shown to be surface specific and proceeds via endwise peeling. Finally, we show that the reaction product terephthalic acid is pure and obtained in high yields.

textile recycling

polyester

depolymerization

peeling reaction

alkaline hydrolysis

Author

Jenny Bengtsson

RISE Research Institutes of Sweden

Anna Peterson

RISE Research Institutes of Sweden

Alexander Idström

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry

Hanna de la Motte

RISE Research Institutes of Sweden

Kerstin Jedvert

RISE Research Institutes of Sweden

Sustainability

20711050 (eISSN)

Vol. 14 11 6911

Subject Categories

Polymer Chemistry

Paper, Pulp and Fiber Technology

Polymer Technologies

DOI

10.3390/su14116911

More information

Latest update

1/10/2023