A new hybrid nanostructured sorbent ZnCl2-MCM-41, was synthesized by a post-synthesis method in toluene as the solvent. To characterize the sorbent, a number of methods were applied, including X-ray diffraction(XRD), nitrogen adsorption-desorption isotherm, Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy(TEM), and scanning electron microscopy(SEM). Characterization demonstrated that sorbent particles are of semi-spherical shape, nanostructured with a754 m2g-1 surface area and a 2.86 nm pore diameter. The Pb(II) removaldepended on several parameters, including the pH of solution, temperature, initial Pb(II) concentration, sorbent dosage, ionic strength, andthe amount of ZnCl2 loaded on the MCM-41 surface. The results showed that the pseudo-second-order model describes the kinetic of sorption better than the pseudo-first-order model. The adsorption continuously increased in the pH range of 2.0–7.0, beyond which the adsorption could not be carried out due to the precipitation of the metal ions. The adsorbent had a considerably high Langmuir monolayer capacity of 479 mgg-1. The adsorption process was exothermic at ambient temperature and the computation of the parameters ΔGº, ΔHº, and ΔSº indicated the interactions to be thermodynamically favorable

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