Mechanism and Activation Energy of Arsenic Removal From Aqueous Solutions

Abstract

This paper presents the mechanism and activation energy adsorption of arsenic (Ase) onto powdered eggshells (PWDEs). The essential compositions and micrograph structure of the PWDEs were determined using standard methods. Adsorption kinetics of Ase onto PWDES were monitored using standard adsorption kinetics models. Effects of pH, particle size, and initial Ase concentrations on the kinetics of Ase adsorption onto PWDES were studied and analysed using analysis of variance (ANOVA). The study revealed acid solubilities were 6.048 % and 6.383 % based on the wet and dried weights respectively, and water solubilities were 0.450 % and 0.536 % based on the wet and dried weights respectively. ΔS° and Ea become more negative or positive with decreasing initial concentration indicating that changes in the selected factors favour the removal process. It was concluded that in the presence of water aluminium, calcium and iron salts undergo displacement reactions. Average cost of producing a kilogram of PDEs was found to be 0.426 USD at the rate of ₦660 per USD.