tailieunhanh - Removal of Cd(II), Cu(II), and Pb(II) by adsorption onto natural clay: A kinetic and thermodynamic study

In this work, we study the elimination of three bivalent metal ions (Cd2+, Cu2+, and Pb2+) by adsorption onto natural illitic clay (AM) collected from Marrakech region in Morocco. The characterization of the adsorbent was carried out by X-ray fluorescence, Fourier transform infrared spectroscopy and X-ray diffraction. The influence of physicochemical parameters on the clay adsorption capacity for ions Cd2+, Cu2+, and Pb2+, namely the adsorbent dose, the contact time, the initial pH imposed on the aqueous solution, the initial concentration of the metal solution and the temperature, was studied. The adsorption process is evaluated by different kinetic models such as the pseudo-first-order, pseudo-second-order, and Elovich. | Turkish Journal of Chemistry Turk J Chem 2021 45 362-376 http chem TÜBİTAK Research Article doi kim-2004-82 Removal of Cd II Cu II and Pb II by adsorption onto natural clay a kinetic and thermodynamic study 1 1 2 1 Brahim ABBOU Imane LEBKIRI Hanae OUADDARI Lamya KADIRI 1 1 1 1 Abdelkarim OUASS Amar HABSAOUI Ahmed LEBKIRI El Housseine RIFI 1 Department of Chemistry Faculty of Science Ibn Tofail University Kenitra Morocco 2 Department of Chemistry Faculty of Science Hassan II University Mohammedia Morocco Received Accepted Published Online Final Version Abstract In this work we study the elimination of three bivalent metal ions Cd2 Cu2 and Pb2 by adsorption onto natural illitic clay AM collected from Marrakech region in Morocco. The characterization of the adsorbent was carried out by X-ray fluorescence Fourier transform infrared spectroscopy and X-ray diffraction. The influence of physicochemical parameters on the clay adsorption capacity for ions Cd2 Cu2 and Pb2 namely the adsorbent dose the contact time the initial pH imposed on the aqueous solution the initial concentration of the metal solution and the temperature was studied. The adsorption process is evaluated by different kinetic models such as the pseudo-first-order pseudo-second-order and Elovich. The adsorption mechanism was determined by the use of adsorption isotherms such as Langmuir Freundlich and Temkin models. Experiments have shown that heavy metals adsorption kinetics onto clay follows the same order the pseudo-second order. The isotherms of adsorption of metal cations by AM clay are satisfactorily described by the Langmuir model and the maximum adsorption capacities obtained from the natural clay using the Langmuir isotherm model equation are and mg g respectively for Cd II Cu II and Pb II ions. Adsorption of heavy metals on clay is a spontaneous and endothermic process characterized by a disorder of the medium. The