Optimizing Electrocoagulation Process for the Removal of Nitrate From Aqueous Solution

Background: High levels of nitrate anion are frequently detected in many groundwater resources in Fars province. Objectives: The present study aimed to determine the removal efficiency of nitrate from aqueous solutions by electrocoagulation process using aluminum and iron electrodes. Materials and Methods: A laboratory-scale batch reactor was conducted to determine nitrate removal efficiency using the electrocoagulation method. The removal of nitrate was determined at pH levels of 3, 7, and 11, different voltages (15, 20, and 30 V), and operation times of 30, 60, and 75 min, respectively. Data were analyzed using the SPSS software version 16 (Chicago, Illinois, USA) and Pearson’s correlation coefficient was used to analyze the relationship between the parameters. Results: Results of the present study showed that the removal efficiency was increased from 27% to 86% as pH increased from 3 to 11 at the optimal condition of 30 V and 75 min operation time. Moreover, by increasing the reaction time from 30 V to 75 min the removal efficiency was increased from 63% to 86%, respectively (30 V and pH = 11). Pearson’s correlation analysis showed that there was a significant relationship between removal efficiency and voltage and reaction time as well (P < 0.01). Conclusions: In conclusion, the electrocoagulation process can be used for removing nitrate from water resources because of high efficiency, simplicity, and relatively low cost.