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Natural bentonite clay (NBC) was activated using nitric acid (HNO₃). Characterization techniques including FTIR, SEM, XRD and BET were employed to examine the morphology of NBC and ABC (activated bentonite clay) sorbents. Comparative application of ABC and NBC to remove heavy metals (Fe²⁺, Zn²⁺, Ni²⁺) from pharmaceutical effluents was investigated under various experimental conditions. The maximum proportional removal by ABC was 88.90, 81.80 and 75.50% at pH 8, and 63.90, 59.60, 58.70% at pH 10 for NBC, both for Zn^2+, Fe²⁺ and Ni²⁺ respectively. The Freundlich multilayer adsorption model and pseudo-second-order kinetics best fit the experimental data, suggesting the formation of multiple adsorption layers via strong ionic and electrostatic interactions. Heavy metals adsorption is more favorable with ABC than NBC, due to the availability of more sorption sites and a larger specific …