The presence of metallic pollutants presents a significant risk to human health, making their removal crucial. Magnetic halloysite nanotube (HNT@Fe3O4) nanocomposite was synthesised via co-precipitation, and then magnetic hydrogel (Fe3O4@HNT-SA and Fe3O4@HNT-CTS) nanocomposites were prepared using chitosan (CTS) and sodium alginate (SA) biopolymers. The structural, morphological, crystalline, surface, and thermal properties of the hydrogels were determined. The favourable adsorption performance of Fe3O4@HNT-SA and Fe3O4@HNT-CTS hydrogels towards As, Cd, Cr, Mo, Pb, Sb and V was established by optimising the factors affecting the sorption process. The results indicated that Fe3O4@HNT-CTS was suitable for the adsorption of As, Cr, Mo, Sb and V, while Fe3O4@HNT-SA had high adsorption affinity for Cd and Pb. The data for the adsorption of target analytes onto the hydrogels were mostly explained by both the Langmuir isotherm model and the pseudo-second order model. The maximum adsorption capacities of Fe3O4@HNT-SA hydrogel for Cd and Pb were 52.2 mg/g and 57.7 mg/g, respectively. On the other hand, the maximum capacities of the Fe3O4@HNT-CTS hydrogel for As, Cr, Mo, Sb, and V were 30.3 mg/g, 28.4 mg/g, 22.2 mg/g, 24.7 mg/g, and 19.9 mg/g, respectively. The Fe3O4@HNT-SA and Fe3O4@HNT-CTS hydrogels effectively removed the respective target analytes from river water samples
