Adsorption of Ni (II) from Water by Natural Bentonite: Studies on Equilibrium Isotherm, Kinetics

Abstract

The aim of this work is to investigate the adsorption potential of commercial natural bentonite in the removal of Ni (II) ions from aqueous solution. The characterization studies were performed using X-ray Diffraction, Fourier Transform Infrared Spectrometer, thermal gravimetric analysis, Differential Thermal Analysis and Fluorescence spectroscopy. Capacity and specific surface areas are also given. The results show that our sample is a sodic montmorillonite who contains some impurities like quartz and calcite. We also studied the effect of thermic and acid activation on the adsorption of Ni (II) on bentonite. Batch adsorption studies were carried out with various initial Ni (II) concentrations, adsorbent dosages, pH, and contact time. The kinetic studies showed that the nickel adsorption process followed a pseudo-second order. The adsorption data were fitted to the Freundlich and Langmuir isotherm models. This behaviour is described by a monolayer Langmuir type isotherm. The adsorption process is found to be a second order kinetics.

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Authors

1. 1Fossil Energy Valorization Laboratory, Chemical Engineering Department, National Polytechnic School
2. 2Ecole Nationale Polytechnique