A TEXTILE-BASED BIOREFINING STRATEGY FOR POLYESTER RECYCLING FROM BLENDED FABRICS VIA BIOLOGICAL METHOD

In the past few decades, there is a constant increase of global fiber production for textile application, around 100 million tonnes in 2016. The lifetime of textile was shortened dramatically with the increase of living standard and thus a growing amount of textile wastes were generated. In the United States alone, exceeding 16 million tonnes of textile wastes have been generated in 2014. In Hong Kong, 306 tonnes of textile waste were generated per day, and 95% of textile waste ended up in landfills, which exerts more pressure on the limited landfill space. Therefore, it is urgent to find an environmentally and economically sustainable process to recycle textile waste. In this work, a novel process for blended textile fabrics recycling was developed with the blended fabrics cotton/polyester 40/60 as feedstock. Firstly, the textile waste was mixed with NaOH and urea at -20 ℃ for 6 h and neutralized to pH 7, followed by rinsing with tap water for 3-5 times and drying in oven for 48 h. Next, the pretreated materials were hydrolyzed with addition of cellulase and ßglucosidase under optimized conditions for 96 h. The final glucose yield was 85% and the purity of polyester fiber was 98.2%. Finally, the recovered polyester was further processed by melt spinning in order to be re-spun into new polyester fibers. The re-spun fully oriented yarn was produced with a tenacity over 3 g/den and an elongation of 20%-40%. The present study demonstrates a novel circular textile waste-based biorefinery strategy with recovery of glucose and polyester as valueadded products.