Removal of Microplastics from Aqueous Medium Using Electrostatically Charged Mustard Seeds: A Sustainable Approach

Polyvinyl chloride (PVC) microplastics (MPs) in water systems pose significant environmental and human health risks due to their persistence and colloidal behaviour. This study explores the triboelectric effect and electrostatic principles as a novel, sustainable method for PVC MPs removal from water using natural mustard seeds. Triboelectric charging was employed to impart a positive surface charge on mustard seeds, enabling electrostatic attraction of negatively charged MPs in water. Experimental results obtained through advanced imaging using optical microscopy, scanning electron microscopy (SEM), field emission SEM (FESEM) and quantitative analysis using Zeta potential measurements and Fourier transform infrared (FTIR) spectroscopy, confirm that electrostatically charged mustard seeds can attract and remove PVC MPs after successive treatment cycles. The analyses revealed a substantial reduction in the PVC MPs load from water. The measured removal efficiency of > 90% demonstrates that the proposed approach has potential in eliminating MPs contaminants at relatively low cost. This work outlines the underlying mechanism and highlights the possible applicability for future municipal and industrial water treatment applications, demonstrating how charge generation, combined with the unique properties of mustard seeds, facilitates a cost effective, and ecofriendly approach for the removal of MPs from aqueous media and provides scope for further investigation toward scale up.