<p>This study investigates the synthesis of a new magnetic adsorbent based on functionalized HY zeolite with a dendrimer-like structure (Fe₃O₄/HYZ@SiO₂–Tris–TCT–DAPT) for the efficient removal of Pb²⁺ and Ni²⁺ ions from aqueous solutions. The adsorbent was prepared by immobilization of Fe₃O₄ followed by surface functionalization to introduce organic groups in several sequential steps. Characterization of the functionalized zeolite by XRD, FT-IR, SEM, EDX-mapping, BET, VSM and TGA confirmed the successful synthesis, preservation of the zeolite structure and its superparamagnetic properties. The adsorption process reached equilibrium for Pb²⁺ and Ni²⁺ ions within 30&#xa0;min and 90&#xa0;min, respectively. The adsorption process followed a pseudo-second-order kinetic model and Langmuir isotherm, indicating a monolayer chemical composition. Thermodynamic results showed that the adsorption was spontaneous and exothermic. Under the optimized conditions, the removal efficiency of 99.1% for Pb²⁺ and 90.6% for Ni²⁺ was achieved. Furthermore, the adsorbent showed reusability with minimal performance degradation after repeated cycles. The enhancement of adsorption performance was attributed to the synergistic effect of magnetic Fe₃O₄ nanoparticles and multifunctional organic groups. These findings indicate that the synthesized magnetic zeolite is a promising, recyclable and efficient adsorbent for the removal of heavy metals from contaminated water.</p> Graphical Abstract <p></p>