Mild hydrolysis and upgrading utilization of waste PET: Preparation of regenerated TPA and MOF materials and study of their adsorption performance

Traditional alkaline hydrolysis is often used for recycling poly (ethylene terephthalate). However, its reliance on harsh conditions such as strong alkalis and high temperatures leads to equipment corrosion and environmental pollution. To address the limitations of harsh traditional hydrolysis, this study presents a mild and eco-friendly strategy using recyclable solid Li 2 CO 3 in an ethanol-water solvent. This method efficiently degrades waste PET into terephthalic acid (TPA) with >99% purity, minimizing equipment corrosion and pollution. Instead of repolymerization, the recovered TPA is upcycled to synthesize MIL-68(Al), a metal-organic framework (MOF) with superior adsorption properties. The resulting MilL-68(Al) demonstrates rapid and high-capacity adsorption for tetracycline (540.54 mg/g within 5 min), fitting Langmuir and pseudo-second-order models. Furthermore, it exhibits robust stability against environmental interference and excellent reusability, maintaining >95% efficiency after five cycles. This work offers a dual solution for plastic waste upgrading and antibiotic pollution control.