Mohammad Irani - Department of Chemical Engineering, Faculty of Engineering, University of Tehran, Tehran, Iran
Mohammad Ali Mousavian - Department of Chemical Engineering, Faculty of Engineering, University of Tehran, Tehran, Iran
Ali Reza Keshtkar - Nuclear Fuel Cycle School, Nuclear Science and Technology Research Institute, Tehran, Iran

In this work, natural diatomite clay of Iran has been used as an adsorbent for removing of lead from aqueous solution in a batch mode. The effect of several variables like pH, contact time, initial concentration and temperature on lead sorption onto the diatomite is investigated. Kinetic data were analyzed using pseudofirst-order, pseudo-second-order and double-exponential models. The equilibrium experimental data were tested with Freundlich, Langmuir and Dubbin-Radushkevich. The maximum adsorption capacity of lead ion for natural diatomite was found to be 25.01 mg/g at T=45 ºC. Thermodynamic parameters showed that thelead sorption onto the diatomite is endothermic and spontaneous for adsorption of lead. Because of low-costand local availability of natural diatomite; this clay has suitable potential for removal of lead ions in practical process

Diatomite, Lead, Adsorption, Kinetic, Isotherm, Thermodynamic