The effect of pH on H₂O₂and nitrate production in the plasma electrolysis process

Plasma electrolysis is the newest method in the formation of environmentally friendly nitrogen fertilizers. Nitrogen fertilizer in the form of liquid nitrate from air injection in a K2SO4 electrolyte solution flowing direct current. Nitrate formation is influenced by the pH conditions of the electrolyte solution. This is related to the equilibrium of nitrate formation, which will decrease with decreasing pH. The results of this study, the effective plasma electrolysis process for the formation of nitrates, was carried out within 60 minutes with the initial acidity level of the K2SO4 electrolyte solution pHo=6. During 60th minutes, the final processes pHt=3, and the nitrate equilibrium shifts to the reactants to become nitrite, so at this point, the process is stopped so that there is no nitrate reduction. The pH condition also affects the formation of H2O2, which represents the presence of •OH as a nitrate forming radical. At pH=6, the amount of H2O2 produced was higher (0.62 mmol/L) than at 8.10 and 12 (0.42 mmol/L, 0.36 mmol/L, and 0.31 mmol/L). Nitrates produced at pH=6 were higher (1889 ppm) than at 8.10 and 12 (1635 ppm, 860 ppm, and 646 ppm).