Batch adsorption experiments were carried out to remove Zn(II) ions from aqueous solutions and water samples using powdered marble wastes (PMW) as an effective sorbent which is inexpensive, widespread, and considered as an environmental problem. The parameters such as solution pH, sorbent and Zn(II) concentrations, stirring times, foreign ions and temperature were investigated. The sorption of Zn(II) ions onto (PMW) is described by Langmuir model. Dubinin-Radushkevich (D-R) isotherm model was

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... so applied to describe the nature of the adsorption of the metal. Thermodynamic parameters, viz. the Gibbs free energy change (∆G º), enthalpy (∆H º) and entropy (∆S º) were also calculated. These parameters indicated that the adsorption process of Zn(II) ions on PMW was spontaneous and endothermic in nature. Under the optimum experimental conditions employed, the removal of ~100% of Zn(II) ions was attained. The procedure was successfully applied to remove Zn(II) ions from aqueous and different natural water samples. The adsorption mechanism is also suggested.