Thermodynamics and Kinetics of CO2 Sorption and Water Remediation on Waste Polyurethane Foam-Derived Hybrids

Converting waste into dual-function materials for both atmospheric and aqueous remediation remains a formidable challenge in realizing a circular economy. Here, we report a chemical upcycling strategy that transforms discarded polyurethane foam into a novel class of sorbents. We demonstrate that recovered waste oligomers can be fundamentally engineered into high-performance materials exhibiting a bifunctional capacity for atmospheric CO2 capture and rapid aqueous phenol removal. By chemically functionalizing polyurethane glycerolysate (GLC) with poly(allyl alcohol) and carbon nanotubes (CNTs), we engineered a series of novel composites wherein waste-derived nitrogen and oxygen functionalities cooperatively act as active adsorption sites. Distinct from physical blends, our optimized PAA-GLC-CNT10 material exhibits a precisely tuned mesoporous network (2.8-4.1 nm) and tailored surface chemistry. This structural refinement enables highly efficient CO2 sorption (2.94 mmol g-1) alongside rapid phenol removal (>99% clearance within 5 min). Elucidating the underlying mechanism through comprehensive spectroscopic characterization (XPS, NMR, FTIR, UV) coupled with machine-learning analysis, we reveal that this exceptional performance stems from the optimal interplay of pore confinement and targeted intermolecular interactions, specifically hydrogen bonding and π-π stacking. This study establishes that recovered waste oligomers effectively serve as surface modifiers, providing a robust pathway to convert chemical recyclates into scalable, high-value materials with dual applicability in aqueous and atmospheric remediation.