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-The removal of heavy metals from wastewater has become an important subject for scientific research. Among the common methods, adsorption has shown good potential to treat contaminated effluents. In this study, the thermally treated clay called "Verde-lodo" was used in the adsorption of silver ions, a metal with wide industrial use and high commercial value. Firstly, the process kinetics was studied in different silver concentrations. The kinetic curves were adjusted by the following models: pseudo-first order, pseudo-second order, intra-particle diffusion, Boyd and mass transfer in the extern film models. The adsorbent before and after process was characterized by the techniques: BET and Helium Pycnometry.

Several studies have focused on the removal and recovery of precious metal ions from industrial wastewater due to their environmental and economic importance. Adsorption on bentonite clays has been shown to possess a high removal potential for several metal ions. We herein investigated the dynamic adsorption of silver using a fixed-bed column and a calcined bentonite clay called Verde-lodo as an adsorbent. A fluid dynamic study was performed to evaluate the adsorption system's metal-ion removal capacity (q u and q t ), the mass transfer zone and the percentage of total removal according to different effluent's flow. Adsorption-desorption cycles were carried out using nitric acid as an eluent to evaluate the useful lifetime of the column. The breakthrough curves were fitted to the Bohart-Adams model (quasichemical). Moreover, the zeta potential was analyzed to explain the difference between the removal capacity obtained for the static and dynamic systems.

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