The "fast fashion" industry is producing ever greater piles of unnecessary waste. One of the key barriers to the recycling of textile waste is the problem of mixed fibre materials. Not only are fibres frequently blended together within products (e.g. polyester-cotton shirts) but even garments made from single materials tend to end up in a single mixed textile waste stream.
Chemical engineers have dreamed up various chemical processes for recycling mixed wastes. Few have been subjected to any kind of sustainability assessment, which is a problem given the need for various chemical reagents, solvents and even energy demanding distillation processes in some of the alternatives.
Life cycle analysts, led by Chalmers University of Technology, have published an examination one of the most promising proposals (the "Blend Re:wind" alkaline hydrolysis process) from an environmental perspective. The results indicate environmental benefits but the need to further optimise the process during scale-up. (Peters et al 2019)
Click here to access the study.