Recycling processes of polyester-containing textile waste–A review

In 2023, the global production of fibres exceeded 124 million tonnes, with polyethylene terephthalate (PET) representing 57 % of this output. However, <1 % of the fibres are made from disposed textiles, thus suggesting ample margins of improvement to close loops and have a circular economy for textiles. Emerging technological innovations for recycling diverse waste streams and increasing the recycling rates are currently being developed within industry and academia. In this work, we present the current state-of-the-art of textile recycling options for PET-containing textiles. We evaluate various end-of-life strategies for textile polyester waste, including incineration, pyrolysis and gasification, mechanical and thermo-mechanical recycling, solvent-based separation, and chemical recycling approaches such as glycolysis, (enzymatic) hydrolysis, methanolysis, aminolysis and ammonolysis. Furthermore, we discuss advantages and disadvantages of the processes with respect to varying feedstock compositions. Our findings indicate a notable increase in publications in recent years, especially on chemical recycling technologies. Continued research is essential to address challenges associated with fibre blends and to better understand the impact of impurities on the performance of different recycling technologies. Environmental assessments of established and emerging technologies are necessary to evaluate the impact and potential role of recycling technologies in enhancing circularity within the textile industry.