In this study, the removal of zinc (Zn2+) from aqueous solutions was investigated using a Na-enriched Brazilian gray clay. The mineral clays were characterized through EDX, XRD analysis and CEC. A finite bath system was used to evaluate the main effects of mechanical agitation (from 100 to 200 rpm), pH values in the range from 6.0 to 8.0 and Zn2+ initial concentrations (from 10 to 50 mg/L) on the removal process capacity. Langmuir and Freundlich isotherm models were applied in order to determine the efficiency of clay used as an adsorbent. According to the obtained results, Langmuir model adjusts very well to the experimental data. Based on the kinetic studies for the Na-enriched gray clay, it was verified that the mechanism corresponds to a predominant pseudo-second order adsorption, presenting a kinetic constant value equal to k = 1.13 (g.min/mg).
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