Polyester/Cotton-Blended Textile Waste Fiber Separation and Regeneration via a Green Chemistry Approach

To effectively recycle polyester/cotton-blended textiles in discarded clothing and enhance resource utilization, this work employs a low eutectic solvent [deep eutectic solvent (DES)] based on metal salt hydrates for the efficient separation of polyester/cotton blends. The DES is synthesized in a specific proportion from triple components, zinc chloride, water, and phosphoric acid. This solvent can selectively dissolve the cotton fibers in mixed textiles without damaging the polyester fiber component. Experimental results from Fourier infrared spectroscopy, X-ray diffraction, and thermal performance analysis suggest that the DES can accomplish efficient separation of polyester fibers and cotton fiber components, with no significant damage to the polyester fiber structure postseparation. Upon separation, the two components can be processed for regeneration and reuse: the separated cellulose can be dissolved again and processed through wet spinning to produce cellulose fibers, while the separated polyester fibers can further undergo melt spinning. This work provides new insights into the green and efficient separation and regeneration of polyester/cotton-blended textiles, potentially enhancing the recycling rate of waste textiles and reducing environmental pollution.