Study on Application of Electrocoagulation Process to Remove Heavy Metals Lead, Cadmium and Chromium from Water

The increasing use of heavy metals for industrial purposes has caused an increment in discharge of these contaminants as industrial wastewater into the environment. Electrocoagulation is a complicated process with several functional mechanisms to remove pollutants. Use of this process as an effective and efficient method to remove heavy metals from water has been recommended.
In this research studied parameters are: reaction time, distance between electrodes, initial heavy metal concentration, electrode material, and inlet voltage and pH value. Then, the effect that any of these parameters was investigated. In order to do that a 5.4-liter pilot from plexiglass with length of 20 cm, width of 15 cm and height of 18 cm with electrodes of iron, aluminum and steel having length and width of 15 cm and thickness of 0.2 cm and voltage between 0 to 48 v and a direct current (DC) power supply was used.
removal efficiency by electrocoagulation is directly related to voltage and reaction time increment, so that the best removal efficiency was occurred in voltage of 40 v and reaction time of 40 min. By increasing the initial concentration of metals from 1 to 50 mg/l, removal percentage of lead, cadmium and chromium was decreased. Most amounts of removal percentage were gained using iron– aluminum electrodes in a condition in which the distance between them was 5 cm and pH value was equal to 3.
Discussion and Due to the excellent efficiency of the electrocoagulation process in removing heavy metals of chromium, lead and cadmium, the feasibility of removing the metals desired by this process is evaluated and can be used as a novel solution in removing metal ions from industrial effluents.