Preparation and characterization of nano Muscovite by intercalation method for adsorption of heavy metals from polluted water

Abstract

In this work, nanomuscovite adsorbents were prepared via intercalation with different organic intercalates (DTAB- TTAB- DTPA- PA- PN). The prepared nanoadsorbents were used to evaluate the removal of Cd2+ and Pb2+ from polluted water. Best nanomuscovite was prepared by Muscovite with DTPA. The selected nanomuscovite was characterized by XRD, TEM, EDX, FTIR and BET surface area. The maximum Cd2+ and Pb2+ removal efficiency of the prepared nanomuscovite ( 91.5% Cd and 97% Pb ) was observed at intial metal concentration 50 ppm, pH 6 for Pb2+ and pH 7 for Cd2+, adsorbent dosage 0.2 g, contact time 60 min, and solution temperature 25oC. Isotherm models (Freundlich, Langmuir, Dubunin–Radushkevich and Temkin isotherm models) were applied for the adsorption of Cd2+ and Pb2+ on nanomuscovite adsorbent. The Langmuir isotherm model was well-fit by the adsorption of Cd2+ and Pb2+ on nanomuscovite. The kinetics of adsorption were validated using the pseudo-first order, pseudo-second order, Elovich, and intra-particle diffusion models.. Adsorption of Cd2+ and Pb2+ on nanomuscovite follows a pseudo-second order kinetic model in all four of the kinetic models. Thermodynamics parameters of Cd and Pb adsorption indicated exothermic and spontaneous processes for Cd2+ and Pb2+. The obtained results were applied to the real wastewater which indicated high Cd and Pb removal.