Fluoride Removal from Aqueous Solution by Electrocoagulation Using Aluminium Electrodes: Isotherm and Kinetic Studies

Abstract

Themain objective of the present study was the removal of fluoride from aqueoussolution by electrocoagulation technique using aluminum electrodes. The effectof various parameters such as current density, time and initial fluoride concentrationwere studied to optimize the conditions. Experimental study showed that maximumremoval efficiency (87.4%) was achieved at the conditions of current density 11 mA/cm2, reaction time 30 min and initial fluoride concentration 10 mg/L. Isotherm models (Langmuir and Freundlich) and kinetic models(pseudo-first order and pseudo-second order) were used to analyze theelectrocoagulation mechanism and characterize the process parameters.Experimental data well fitted with Langmuir and Freundlich isotherm equationsand results of the kinetic study indicated that pseudo-second order kineticmodel give higher correlation coefficients for different conditions.