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Synthesis of MIL-53 (Al) MOF from post-consumer multilayer bags (MLB) |
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| รหัสดีโอไอ | |
| Title | Synthesis of MIL-53 (Al) MOF from post-consumer multilayer bags (MLB) |
| Creator | Orathai Kangkamanee |
| Contributor | Paiboon Sreearunothai, Advisor |
| Publisher | Thammasat University |
| Publication Year | 2568 |
| Keyword | Polyethylene terephthalate (PET) depolymerization, Metal-organic frameworks, Multilayer bag (MLB), MIL-53(Al), CO₂ adsorption |
| Abstract | This research investigates the upcycling of two categories of post-consumer plastic waste, multilayer bag packaging (MLB) and polyethylene terephthalate (PET) bottle waste, into high-value porous adsorbent materials, specifically the MIL-53(Al) metal-organic framework (MOF). Multilayer composite packaging represents a global waste management challenge, as it is among the least recyclable and most environmentally persistent plastic formats due to its complex aluminum-polymer laminate structure. Unlike conventional PET or polyethylene (PE) packaging, multilayer bags consist of adhesive layers, aluminum foil, and mixed polymers that are difficult to separate using mechanical recycling methods, often resulting in landfill disposal, incineration, and associated emissions. This study proposes an alternative strategy to valorize such waste through selective chemical extraction, separation, and subsequent MOF synthesis using recovered precursors. Three MIL-53(Al) samples were synthesized for comparative analysis: a commercial reference, a PET-derived sample, and an MLB-derived sample. Terephthalic acid (TPA) extracted from PET and multilayer bags was purified and used as the organic linker, while aluminum recovered from multilayer packaging served as a secondary metal source. Comprehensive characterization confirmed that all synthesized materials exhibited the structural fingerprint of MIL-53(Al). Fourier-transform infrared (FTIR) spectroscopy verified the coordination between Al-O clusters and terephthalate linkers through characteristic carboxylate bonding, while X-ray diffraction (XRD) analysis confirmed the crystalline structure in all samples. Nitrogen adsorption analysis revealed that the BET surface areas of the commercial, PET-derived, and MLB-derived samples were approximately 564.5, 999.1, and 1064.2 m2·g-1, respectively. The MLB-derived MIL-53(Al) exhibited the highest surface area; however, adsorption behavior indicated that gas uptake is not governed solely by surface area. Carbon dioxide (CO2) adsorption measurements at 25 °C showed uptake capacities of 1.28 mmol· g-1 for the commercial sample, 2.56 mmol· g-1 for the PET-derived sample, and 2.29 mmol· g-1 for the MLB-derived sample. The enhanced performance of waste-derived samples suggests improved CO₂ affinity, likely due to increased porosity.These findings demonstrate that multilayer packaging waste, previously considered non-recyclable, can serve as a viable precursor for high-performance CO₂ adsorbents. This waste-to-MOF approach offers a promising pathway to reduce landfill burden and incineration emissions while supporting circular material strategies for carbon mitigation. Therefore, waste-derived MIL-53(Al) materials present a sustainable and effective alternative to fully commercial adsorbents. |
