<p>The epoxidation of olefins is a pivotal reaction in organic synthesis, yielding epoxides that serve as essential intermediates in the production of pharmaceuticals, polymers, and fine chemicals. Conventional epoxidation methods often employ hazardous oxidants and nonrecyclable catalysts, leading to significant environmental and economic drawbacks. This study presents a novel, eco-friendly approach for the aerobic epoxidation of olefins utilizing recyclable NiFe₂O₄@SO₃H@AC magnetic nanoparticles. The catalyst comprises nickel ferrite (NiFe₂O₄) for magnetic separability, sulfonic acid groups (SO₃H) to provide acidic catalytic sites, and activated carbon (AC) to enhance surface area and adsorption properties. Employing molecular oxygen as the terminal oxidant, this system offers a sustainable alternative to traditional methods. The NiFe₂O₄@SO₃H@AC catalyst demonstrates high activity and selectivity across a range of olefins, with excellent recyclability, maintaining performance over multiple reaction cycles. Characterization techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FT-IR), confirm the structural integrity and functionality of the catalyst. This work advances the field of green catalysis by providing an efficient, recyclable, and environmentally benign method for olefin epoxidation, addressing critical challenges in sustainability and industrial applicability, and instilling confidence in its reliability.</p> Graphical abstract <p></p>