MODELING OF TEXTILE WASTEWATER ELECTROCOAGULATION VIA ADSORPTION ISOTHERM KINETICS

Abstract

This study has been carried out to determine the feasibility of COD adsorption on iron coagulant by EC process, and to find a mathematical model using kinetic isotherms. Experiments were carried out to treat a high strength wastewater of textile industry located in Al-Hilla-Iraq using a batchwise mode. A well-rounded range of current density was tested and the COD removal percent has reached a maximum value of 85.2 under c.d. of 20mA/cm2. It was attempted to fit the experimental data with the popular adsorption isotherms Langmuir, Freundlich and Temkin, hense the mechanism of adsorption with the effect of individual parameters on the efficiency of electrocoagulation have been critically examined. Two well-known coagulant mechanisms were modeled with the kinetic equations utilizing the result from experiments relative to EC of COD removal for five set of experiments. It has been found from the present analysis that the adsorption isotherm with iron (II) and iron (III) hydroxides combined to generate hydroxo cationic-anionic complex of green rust mechanism, can be described by Langmuir isotherm equation which gives a preferable fit of experimental data than the Freundlich and Temkin isotherm model equations.