(388a) Efficient Removal of Micro- and Nano-Plastics from Water Using Ionic Liquid-Based Liquid-Liquid Extraction

In the 21^st century, Micro- and Nano-plastics (MNPs) are the potential emerging plastic-related pollutants that have adverse impacts spreading across all the environmental media, including fresh water. The current conventional water treatment methods, such as coagulation, flocculation, filtration, photocatalytic degradation, and microbial bioremediation, showed a lack of efficiency in the removal of different MNPs. Hence, new removal techniques are needed to be developed. The Liquid Liquid extraction (LLE) method is a promising separation technique for efficiently removing MNPs in water treatment. In the present work, we report the removal of two types of polystyrene (PS) MNPs from water, including synthesized micron-size (>1 µm ) PS and commercial sulfonated PS (nano-size, ~70 nm) using a hydrophobic IL [C₈mim][Tf₂N]. The extraction process showed more than 99% removal of both PS MNPs at the ratio of 1:40 (vol:vol) IL/water for the removal of 100 ppm PS MNPs from water. The extraction process using other volume ratios revealed 98.89%, 96.26%, and 98.60 % removal for the ratios of 1:100, 1:200, and 1:1000 (vol:vol) IL/water, respectively. The kinetic data showed that the maximum adsorption reached after 3 h. In addition, the extraction efficiency of PS MNPS was evaluated in the presence of 2000 ppm NaCl, and ~ 99.36 % removal was achieved, showing the selectivity of [C₈mim][Tf₂N] towards PS MNPs