Upcycling PET Waste into High-Performance Metal–Organic Frameworks: Sustainable Synthesis of MIL-53(Al) for Gas Separation and Storage

Abstract This study investigates the potential of upcycling polyethylene terephthalate (PET) waste into high-valuable functional materials, specifically focusing on the synthesis of metal–organic frameworks (MOFs). Terephthalic acid (TPA), obtained through acidic hydrolysis of post-consumer PET waste, was utilized as an organic linker to synthesize MIL-53(Al)-R, a well-known aluminum-based MOF. The synthesized MIL-53(Al)-R exhibits the same crystal structure, morphology, and porosity as conventional MIL-53(Al)-C, with gas adsorption performance comparable to existing literature values. These findings validate the feasibility of using recycled PET as a viable feedstock for MOF production and highlight the potential of waste-derived MIL-53(Al)-R as an eco-friendly adsorbent for gas separation and storage applications. The study not only underscores the functional performance of MIL-53(Al)-R but also promotes a sustainable strategy for plastic waste valorization. By transforming environmental pollutants into high-performance materials, this work supports green chemistry initiatives and contributes to the development of circular economy approaches in materials science and chemical engineering.