Removal of oil from biodiesel wastewater by electrocoagulation method

An attempt has been made to remove oil and grease (O&G) from biodiesel wastewater as well as O&G and turbidity in the presence of H2O2 and polyaluminum chloride (PAC), as a coagulant-aid by an electrochemical method using iron as sacrificial electrodes. The effects of current density, amount of hydrogen peroxide using as an oxidizing agent and addition of coagulant-aid, on percent removal and energy consumption have been investigated. The removal efficiency of O&G was in the range of 62-86%, whereas O&G removal was 100% in the current density range of 10-12.5 mAcm(-2) depending on the concentrations of H2O2 and coagulant aid. It is obtained that electrocoagulation in the absence of coagulant aid and oxidant is not too efficient for the treatment of this type of wastewater.