Study of kinetic models of olive oil mill wastewater treatment using electrocoagulation process.

This study investigates the kinetic model of chemical oxygen demand (COD) removal from olive oil mill synthetic wastewater through electrocoagulation using stainless steel and aluminum as a cathode and anode electrodes, respectively. The one-factor method was used to evaluate interactions between the operational parameters that affect COD removal. A reactor with a volume of 250 mL was utilized to perform the process. The optimal conditions with 99% COD were found to be the current density of 12.5 mA cm^-2, 400 mg L^-1 NaCl as supporting electrolyte, initial COD concentration of 17,500 mg L^-1, and operation time of 60 min. The highest efficiencies of COD removal were achieved at pH values of 5 and 9 using stainless steel and aluminum electrodes as cathode and anode, respectively. The results demonstrated a direct relation between the coagulant adsorption rate and efficiency of COD removal by olive oil. According to the obtained results, the process follows an intra-particle diffusion kinetic model, in which absorption capacity is high at the beginning, and removal efficiency increases over time. [ABSTRACT FROM AUTHOR]