A Comparative Study Using Aluminum and Iron Electrodes for the Electrocoagulation of Palm Oil Mill Effluent to Reduce its Polluting Nature and Hydrogen Production Simultaneously

This study was designed to compare the effectiveness of Aluminium (Al) and Iron (Fe) as electrodes to reduce the polluting nature of Palm Oil Mill Effluent (POME) and simultaneous hydrogen production using electrocoagulation (EC). Electrocoagulation of raw POME and anaerobically pretreated POME was performed using Direct Current (DC) electricity of 2.0, 3.0, and 4.0 volts in a reactor volume of 20 liters. The results of raw POME treatment reveal that the chemical oxygen demand (COD) and turbidity was decreased around 57.66% and 62.5%, respectively, using Al electrode. However, the use of iron electrodes could reduce the COD and turbidity of raw POME about 35.3% and 43.10%, respectively. The reduction in polluting factors of the raw POME was accompanied with the production of 42% and 22.8% of hydrogen gas concentration using Al and Fe electrodes, respectively. On the other hand, the results of Electrocoagulation of POME which was pretreated in anaerobic pond show that the COD was decreased around 62.35% and 59.41% using Al and Fe respectively, and turbidity was reduced up to 90.55% and 76.96% using Al and Fe respectively. The concentration of hydrogen gas yielded as a result of EC of anaerobically pretreated POME was around 31.37% and 25.6% using Al and Fe respectively as electrodes. Removal of pollutants from POME using Electrocoagulation is faster than some other existing processes and requires a relatively small area as compared to the conventional anaerobic treatment in pond system which is potential source of green house gases.