Development of crosslinked polyvinyl alcohol nanofibrous membrane for microplastic removal from water

Abstract

This study presents the development of an innovative nanofibrous membrane to remove microplastics (MPs) from drinking water. This membrane exhibits additional functionality in removing lead (Pb), highlighting its promising potential for utilization as a point-of-use (POU) device. The polyvinyl alcohol (PVA) nanofibrous membranes are crosslinked using glutaraldehyde, and their efficiencies in the removal of MPs are evaluated. The results show that crosslinking the 7 and 10 wt% PVA nanofibers increases their average diameters to 330 and 581 nm, respectively, and enhances their surface area. The treatment efficiency of crosslinked PVA fibrous media is evaluated using polyethylene (PE) (5 μm ≤d ≤ 25 μm) and polystyrene (PS) MPs (d ≤ 1 μm). The filtration efficiencies of both 7 and 10 wt% c-PVA nanofibrous media are found to be 99.8% ± 0.1% in the removal of PE MPs at pH 8. Further examination of the filtration efficiency in the removal of PS MPs shows that the highest removal efficiency achieved was 77.3% ± 1.4% at a pH of 6. Additionally, the lead removal efficiency of this fibrous membrane in flow-through experiments is examined. Results show a pH-dependent lead removal efficiency, in which the greatest efficiency of 69% is found at pH 6.