An Eco-friendly Approach for the Separation and Reusage of Pre-consumer Polycotton Textile Waste

One of the most challenging features of textile recycling is the widespread use of mixed fibre blends, which hardens the task of effective separation. A mixture of aqueous sodium hydroxide and a cosolvent was applied to a polycotton pre-consumer fabric to promote the chemical separation of polyester (PES) and cotton (CO). The feasibility of reusing the hydrolytic solutions was tested, where dimethyl sulfoxide (DMSO) and 2-propanol allowed the reusage of the hydrolytic solution for up to 3 consecutive cycles when applied to pristine material. The recovery of pure terephthalic acid (TPA), after treatment at 50 °C followed by vacuum filtration, achieved yields ranging from 65 to 69%. No further purification was required in 75% of the tested conditions. Through this environmentally sustainable procedure, a method was proposed that could facilitate the development of a scalable process for the TPA recovery from polycotton textiles. This approach aims to reduce both textile waste production and the need for the de novo synthesis of TPA.