Upcycling microfiber waste from wastewater into acoustic panels: a sustainable solution for sound absorption

Microfibers (MFs) are released into the environment during the entire life of textile materials, from manufacturing to disposal. It is evident that micro-sized wastes are just as significant as macro-sized ones, and this issue should be prioritized. The use of textile waste in sound insulation materials is increasingly gaining attention. However, conventional sound absorption materials, such as fiberglass, polyurethane, and melamine foams, offer high-performance acoustic properties, but are derived from non-renewable resources and contribute to environmental degradation. This study aims to develop environmentally friendly fibrous sound absorption panels by reusing MF waste generated during textile finishing processes. Waste MFs used within the scope of the study were collected from a textile finishing process’ wastewater containing a variety of fibers, including wool, cotton, acrylic, polyamide, polyester, polypropylene, and viscose by filtration method and blended with polyester fiber as a binder. Then, acoustic panels were produced using a hot press technique by varying the panel thickness, density, and binder fiber ratio, and the physical, chemical, morphological, and acoustic properties of these panels were tested. Findings revealed that thickness emerged as a critical factor, with the thickest samples exhibiting the highest sound absorption coefficient (0.9 at 3000 Hz). Moreover, an increase in sample density correlated positively with enhanced sound absorption values, while the binder fiber ratio demonstrated a negative impact. Additionally, all samples exhibited hydrophobic characteristics, showcasing water resistance. The statistical analysis of sound absorption performance was conducted using one-way ANOVA and Tukey’s honestly significant difference test, with the results visualized through boxplots. Compared to conventional materials, the developed MF-based panels provide an eco-friendly alternative by reducing reliance on virgin synthetic materials while achieving competitive sound absorption properties. This study enables sustainable waste management in the textile industry and the reuse of MF waste, providing alternative and environmentally friendly solutions to currently used sound absorption materials. While the recyclability and reuse potential of these panels remain promising, further research is needed to evaluate their long-term mechanical performance, resistance to environmental degradation, and practical implementation in real-world applications. Future investigations should focus on optimizing large-scale production processes and assessing the environmental footprint of these materials throughout their lifecycle.