Removal of Nitrate from Aqueous Solutions by Batch Electrocoagulation Processes Using Al and Fe Plate Electrodes

Öz

Nitrate (NO₃^-) is the most common water pollutant in the world, which has a serious threat to human health due to its high solubility in water. Electrocoagulation (EC) process is an impressive method for removal of pollutants from water. This study is focused on the mechanism of NO₃^- removal from aqueous solutions by electrocoagulation process with using aluminum (Al) and iron (Fe) electrodes. Effects of operational parameters such as electrode material, pH and conductivity on the EC process were evaluated. The process carried out by batch method at room temperature (25 ºC). The experimental results for Al–Al (anode-cathode) electrode reveal that nitrate removal efficiencies are 85.94% and 75.29% at 240 min reaction time, for pH of 3 and 10, respectively. Under the same conditions, for Fe-Fe (anode-cathode) electrode combination, the removal efficiencies are 23.1% and 2.66% at pH of 3 and 10, respectively. NO₃^- removal process was carried out at 5V-1A electrical current. According to the results of the study, it was observed that the Al plate electrode was better than Fe plate electrode in NO₃^- removal. In addition, electrocoagulation at low pH was found to be more effective for nitrate removal in the Al-electrode-operated reactor. In addition, pH values and nitrate removal percentages at Al-electrode-operated reactor increased continuously during 240 minutes at low initial pH. On the iron electrode, steady changes were not observed for pH and nitrate removal rates during process period. 

Anahtar Kelimeler

• Nitrate,Electrocoagulation,Batch method

Kaynakça

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