Abstract

Kinetic studies of adsorption of heavy metals (Pb (II), Cu(II), Cd(II) and Zn(II)) on local clay soils from four different locations in Ekiti state have been studied using static batch experimental method. The major factors affecting the heavy metal ions sorption on local clays were investigated. The experimental data were correlated with adsorption isotherm and kinetic equations using linear regression analysis. The plots of the amount of adsorbate adsorbed against equilibrium concentration or mass of dosage of clay or time showed two distinct segments. Firstly, nearly a straight line plot at low concentration and secondly a flat or plateau portion at high concentration were observed. The monolayer concentration of the adsorbent was calculated. Langmuir isotherm was found to correlate the adsorption data better than the Freundlich isotherm. The parameters in these isotherms were evaluated and fully discussed. The adsorption kinetic data were correlated with three functions. The Olaofe proposed function (R²= 97.5 - 99.0 %) was found to be the best followed by Simple Elovich function (R²= 84.5 - 95.9 %) and the least was the power function (R²= 84.3 - 93.1%) .The parameters in the functions and statistical data were reported and fully discussed. The present report has shown that local raw Nigerian clays can be used as adsorbents.

This work is licensed under a Creative Commons Attribution 4.0 License.