Abstract

Cobalt (II) Removal from Aqueous Solutions by Adsorption onto Molecular Sieves

Author(s): G. Babu Rao, M. Krishna Prasad and Ch. V. R. Murthy

Cobalt is a heavy metal that is commonly used in industrial processes and used in batteries and tanning activities. Time-dependent experiments were carried out to study the adsorption kinetics of cobalt (II) ions onto 3 Å molecular sieves in batch conditions at room temperature. The influence of contact time, initial solution pH, initial cobalt (II) concentration, adsorbent dosage and temperature was studied in batch experiments. The experimental data was fitted to pseudo-first (Lagergren model) and pseudo-second order kinetics. According to the modelling, experimental data is better resembled to the pseudo-second order kinetics as shown by its correlation coefficient, indicating that 6 hrs are needed to reach equilibrium. The adsorption data were confronted by using both Langmuir and Freundlich classical adsorption isotherms. The experimental data fitted the Freundlich isotherm from the correlation coefficients.