Normal-hexane treatment on PET-based waste fiber depolymerization process

Abstract

Abstract The global increase in polyethylene terephthalate (PET)-based waste fiber poses a persistent environmental risk. While efforts have been made to repurpose waste fibers into bags, clothing, and building materials, the depolymerization process to extract pure raw materials for recycling remains underdeveloped. This study investigates the impact of normal hexane treatment on the purity of terephthalic acid (TPA) recovered from wastewater containing sodium terephthalate, ethylene glycol, and impurities generated during polyester fabric weight reduction or waste fiber recycling processes. Nuclear magnetic resonance analysis of the recovered TPA (rTPA) revealed a maximum purity of 99.81%, suggesting the effective removal of diverse contaminants such as adhesives and surfactants present in waste fibers through normal hexane and activated carbon treatments. This research contributes to the development of efficient and sustainable PET waste fiber recycling processes, highlighting the potential of normal hexane treatment in enhancing the purity of rTPA.