TP-APTES-TEOS superhydrophilic coating transforms waste plastic bottles into valuable resources for efficient oil-water separation

Plastic pollution and the treatment of oily wastewater have become significant challenges in the field of environmental protection. This study presents a method for fabricating electrospun membranes from waste polyethylene terephthalate (PET) beverage bottles, which are surface-modified by co -depositing tea polyphenols (TP), 3-aminopropyltriethoxysilane (APTES), and tetraethoxysilane (TEOS). The resulting superhydrophilic membrane, denoted as PET-T-100, exhibits excellent mechanical properties and structural stability due to the optimization of precursor solution composition and electrospinning parameters. The modified membrane shows a water contact angle of 0° in air and an underwater oil contact angle of 161°, demonstrating outstanding wettability. In oil-water separation experiments, PET-T-100 achieves a separation efficiency of over 99.5 % for various oil-water mixtures, and over 98 % for emulsions, maintaining stable wettability and separation performance even in harsh acidic, alkaline, and saline environments. This study provides an efficient and environmentally friendly approach for the high-value utilization of waste PET and offers a novel strategy for the development of high-performance oil-water separation membranes and environmental remediation technologies.