Combination of Mechanical Treatment and Enzymatic Hydrolysis During Post-Consumer Cotton Waste Processing

With the continuously increasing volume of textile waste and the limitations of current recycling strategies, there is a growing need for the development of environmentally sustainable and efficient processing methods. Cellulose derived from post-consumer textile waste represents a promising and cost-effective substrate for enzymatic hydrolysis due to its abundance and low market value. This study investigates the synergistic effect of a cellulase enzyme mixture combined with wet rotor milling to enhance glucose yields during the enzymatic hydrolysis of cotton-based textile waste. The impact of mechanical energy input is assessed by varying milling durations in the presence and absence of enzymes. Enzyme-assisted milling enables a streamlined, single-step process, increasing glucose yield by approximately 12% compared to conventional hydrolysis for 6 h. Two iterative cycles of milling followed by incubation in a feed tank are evaluated. The highest glucose conversion (38%) is achieved by combining a premilling step with iterative cycles of milling performed with minimal milling time and subsequent enzymatic hydrolysis. Extended milling times reduce enzymatic activity, suggesting potential inhibitory effects under certain conditions. Overall, the findings support that integrating enzymatic hydrolysis into milling operations is a viable strategy for the partial recycling and valorization of textile waste.