The accumulation of plastic wastes has become a global environmental issue, because of their ever-growing production, slow degradation, and potential environmental hazards. Consequently, reducing their presence in the environment by upcycling has sparked tremendous research interest. Herein, we report the valorization of poly(ethylene terephthalate) (PET) plastic wastes to produce nanofibrous adsorptive membranes for their applications in oil removal. In this study, plastic wastes derived from PET bottles were dissolved in trifluoroacetic acid (TFA) or a TFA/ dichloromethane (DCM) binary solvent system and then electrospun into nanofibrous recycled PET (rPET) membranes. The nanofiber morphology was tuned by adjusting the polymer concentration. The nanofibers produced via electrospinning from TFA solutions were more uniform than those produced using TFA/DCM. The influence of acid-mediated recycling on the PET structure was explored via thermogravimetric and X-ray photoelectron spectroscopy analyses. A dynamic mechanical analysis showed that the membranes exhibited high flexibility with effective Young's moduli. The sorption capacities of the nanofibrous PET membranes for crude oil, diesel, gasoline, and pump oil were 22.9 ± 2, 19.6 ± 1.8, 11.1 ± 1, and 19.3 ± 1.6 g g −1 , respectively. The membrane could be recycled by squeezing and reused five times for oil removal while maintaining an sorption capacity of >75%. After the sorption tests, an apparent increase in the fiber diameter was observed due to the oil uptake into the fiber matrix. The present study provides a sustainable solution to plastic and oil pollution management, minimizing the production of new carbonbased materials and lowering carbon emissions. This work aligns with the United Nations' Sustainable Development Goals, specifically, Goal #12 on responsible consumption and production and #14 on life below water.

The electrospinning of polymer nanofibers has received significant attention owing to their high surface-area-tovolume ratio, high porosity, adjustable pore size and texture, and highly interconnected porous structure. In particular, the electrospinning of biodegradable cellulose acetate (CA) nanofibers has sparked interest in diverse applications, including drug delivery systems, scaffolding for tissue engineering, air filtration, and affinity membrane systems. However, the electrospinning process has been mostly performed using toxic and hazardous solvents and additives. We developed electrospun CA nanofibers using a green solvent system comprising dimethyl carbonate and cyclopentanone. The use of green additives, namely, tetrabutylammonium bromide salts and sophorolipid-based biosurfactants, obtained from honey yeast, substantially improved the spinnability of the CA solution. Moreover, the nanofiber diameter and porous texture were tunable by adjusting the solvent ratio. Pore generation was induced using volatile dimethyl carbonate, which quickly evaporated from the fiber jet. Molecular dynamics simulations demonstrated that the electrospinning process can be divided into three stages. The addition of the biosurfactant facilitated the evaporation process and improved the uniformity of the nanofibers. Furthermore, the nanofibers can be degraded using esterase and cellulase enzymes. To summarize, the electrospinning of ultrafine CA porous nanofibers with tunable morphology was achieved using green solvents and additives.

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