Synthesis, Characterization and Application of Zn/Al-CO3 ¬for the Removal of Lead Ions
N. Ayawei *
Department of Chemical Sciences, Niger Delta University, Wilberforce Island, Bayelsa State, Nigeria
A. K. Inengite
Department of Chemical Sciences, Niger Delta University, Wilberforce Island, Bayelsa State, Nigeria
D. Wankasi
Department of Chemical Sciences, Niger Delta University, Wilberforce Island, Bayelsa State, Nigeria and Applied Chemistry and Nanoscience Laboratory, Department of Chemistry, Vaal University of Technology, P.O.Box X021, Vanderbijlpark, South Africa
E. D. Dikio
Department of Chemical Sciences, Niger Delta University, Wilberforce Island, Bayelsa State, Nigeria and Applied Chemistry and Nanoscience Laboratory, Department of Chemistry, Vaal University of Technology, P.O.Box X021, Vanderbijlpark, South Africa
*Author to whom correspondence should be addressed.
Abstract
In the present work, Zn/Al layered double hydroxide of ratio 2:1 was synthesis by co-precipitation method from their nitrate salts and utilized as adsorbent for the removal of lead ions from aqueous solution. The synthesized Zn/Al-CO3 was characterized by SEM, XRD and FTIR. The effect of various parameters such as contact time, initial concentration and variable temperature were investigated. The results show that the adsorption process was depended on contact time rather than temperature and concentration. Studies of the essential thermodynamic parameters shows that the adsorption process was rapid, exothermic and spontaneous and also fitted both Langmuir and Freundlich isotherm. The results of various kinetic models are zero-order kinetics model R2 =1, second-order kinetic model R2 = 0.998 and pseudo-second order kinetics model R2 = 0.999.
Keywords: Lead adsorption, isosteric heat of adsorption, activation energy, layered double hydroxide, kinetics, adsorption isotherms