Sustainable valorization of 3D printing waste: Electrospun colored PLA nanofibers for high-performance oil adsorption and regeneration

The escalating waste generation from multicolored 3D printing polylactic acid (PLA), presents a significant recycling challenge due to color incompatibility for conventional reprocessing into filament spools. To address this, we explored an innovative approach by repurposing this waste PLA into high-performance nanofibrous adsorbent mats for oil spill remediation. Nanofiber mats were successfully electrospun from various colored PLA waste materials dissolved in a suitable solvent system incorporating a volatile component to enhance porosity and surface area. The resulting nanofiber mats were comprehensively characterized using scanning electron microscopy (SEM) to determine fiber morphology and fiber-to-bead ratio. Energy-dispersive X-ray spectroscopy (EDAX) confirms that colorants and additives introduce trace elements that influence fiber morphology. Fourier Transform Infrared Spectroscopy (FTIR) to identify any structural alterations post-electrospinning compared to the original materials. The oil adsorption capacities of nine colored PLA nanofiber mats and one industrial-grade PLA nanofiber mat were evaluated. The Transparent filament nanofiber mats exhibited exceptional performance, reaching up to 92.4 g/g for silicone and 81.6 g/g for cooking oil. A mixed blend nanofiber mat also demonstrated superior adsorption, 64.24 g/g for cooking oil, nearly doubling L175's capacity. The samples retained up to 82.1 % of their initial n-hexane adsorption capacity over seven cycles. The regeneration of initial adsorption capacity was achieved upon recycling multi-cycled nanofiber mats through re-dissolution and re-electrospinning, validating the reversibility of performance loss and the robustness of active sites. This study highlights a sustainable pathway for valorizing challenging-to-recycle multicolored 3D printing waste into effective, reusable, and recyclable materials for environmental remediation.