Metaalem Shibabaw2025-12-152025-01-01wkuhttps://rps.wku.edu.et/handle/123456789/46687This study synthesized magnetite nanoparticles using an aqueous extract of Catha edulis leaf in a green manner. The effectiveness and ability of the resultant nanoparticles in removing Methylene Blue dye were also assessed. Utilizing SEM, FTIR, P-XRD, and UV-DRS spectroscopy, the produced nanoparticle was examined. According to the XRD data, the average particle size of the produced magnetite NPs was 9.05 nm. The outcome confirmed that Fe3O4 nanoparticles had absorbance maxima at 364 nm, and for samples of produced magnetite nanoparticles, various functional groups were discovered to be connected with the plant extract. The produced Fe3O4 NPs displayed a variety of morphologies and microstructural features for Fe3O4 nanopowder. In addition, the SEM images of the Fe3O4 NPs showed that the nanoparticle morphology was uniform in structure. Using the batch adsorption method, the effectiveness of the adsorbent was assessed by adjusting several parameters, including pH (3–9), adsorbent dose (20–80 mg), initial adsorbate concentration (5 mg/L–20 mg/L), and room temperature contact time (30–90 minute). Optimal removal (99.25%) was achieved at pH 9, using 20 mg of adsorbent, 50-minute contact time, and an initial methylene blue concentration of 5 mg/L. The Langmuir isotherm model and pseudo-second-order kinetics model best described the experimental data (R² ≈ 1). This research suggests that the biosynthesized Fe₃O₄ nanoparticles show significant potential in the removal of methylene blue dye from aqueous solutions.en-USMagnetite NPsGreen synthesisWaste waterisotherm modelkinetics model.Thesis