Efficient Removal of Heavy Metals, Dyes, and Contaminants from Industrial Wastewater Using Chitosan-Coated Fe3O4 Nanocomposites: Biosynthesis, Characterizations, and Performance Evaluation

Industrial wastewater containing heavy metals, toxic compounds, and dyes poses significant environmental concerns. These substances harm aquatic and terrestrial life, making their removal essential for safeguarding biodiversity, ecosystems, and human health. This study focused on synthesizing Fe3O4 nanoparticles (NPs) and their chitosan-coated composite (CS/Fe3O4 NC) for effective wastewater treatment. The NPs were synthesized using the aqueous leaf extract of Laurus nobilis and then coated with chitosan extracted from shrimp. Characterization analysis confirmed the spherical morphology of both Fe3O4 NPs and CS/Fe3O4 NC, with average sizes of 21.3 nm and 28 nm, respectively. The Fe3O4 NPs and CS/Fe3O4 NC exhibited optical bandgap energies of 2.62 eV and 1.81 eV, respectively, indicating their potential as efficient photocatalysts. Photocatalytic efficiency was evaluated using methylene blue (MB) and ortho-toluidine blue (O-TB) dyes. After 75 min, CS/Fe3O4 NC achieved degradation rates of 99% for MB and 98.4% for O-TB, surpassing the rates of 79% and 60.0% achieved by Fe3O4 NPs alone. This highlights the superior performance of CS/Fe3O4 NC in dye degradation. Moreover, Fe3O4 NPs and CS/Fe3O4 NC were effective in removing heavy metals from petroleum water, achieving a remarkable 100% removal efficiency within 30 min. The removal of oil in water was 86% for Fe3O4 NPs and 90% for CS/Fe3O4 NC, while the reduction in total suspended solids was 71% and 78%, respectively. Overall, the synthesized Fe3O4 NPs and CS/Fe3O4 NC demonstrate promising potential for wastewater treatment by efficiently degrading dyes and removing heavy metals, oil, and suspended solids.