Synthesis and Characterization of Hemp Oil-Impregnated Chitosan-Polyvinyl Alcohol Hydrogels for Synergistic Copper (II) Ions Removal from Water

The escalating global crisis of water scarcity, exacerbated by the increasing prevalence of heavy metal contamination from anthropogenic activities, necessitates the development of innovative and sustainable remediation technologies. Recognizing the inherent metal-binding capabilities of Cannabis sativa L. (hemp), this study introduces a novel approach for copper(II) ion removal from aqueous solutions. We investigated the synergistic potential of combining hemp-derived cannabinoids with chitosan-polyvinyl alcohol (PVA) hydrogels to create a bio-based adsorbent. Hemp oil, rich in cannabinoids, was incorporated into chitosan-PVA hydrogels synthesized to enhance mechanical stability. The resulting hemp hydrogels (HHGs) were characterized using Fourier Transform Infrared Spectroscopy (FTIR), confirming the integration of the oil within the hydrogel matrix. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) analysis of copper-contaminated solutions treated with HHGs over 24 hours demonstrated a reduction in copper ion concentration, suggesting a biosorption mechanism. Swelling studies revealed an inverse relationship between hemp oil content and water uptake capacity. Thermal studies showed excellent stability amongst gel types. This work establishes the feasibility of utilizing hemp-modified hydrogels as a promising avenue for heavy metal removal, paving the way for future optimization of these bio-composites in both drinking water purification and industrial wastewater treatment applications.