The Effects of pH and Humic Acid on the Amounts of Ammonium and Nitrite from Water Denitrification Process Using Zero Iron Nanoparticles

Nitrate is one of the most widespread water supplies in the world and one of the most important indicators of drinking water quality. So far, several methods have been used to remove organic and inorganic pollutants from water, that has resulted in the increasing application of iron nanoparticles. Therefore, in this study, the effect of acidity and soluble organic matter on the formation and stability of secondary compounds of nitrate reduction by application of Nanoparticles Zero Iron (nZVI) in vitro conditions is evaluated. In this study, the ability of various levels of zero iron nanoparticles to stabilize on gravel particles (1, 1/5 & 2 mg/l) in the complete recovery of nitrate to ammonium and the formation of nitrite in different acidity (3-4-5) and three concentrations of humic acid (0-0/25-0/75 mg/l) was evaluated. Based on the results, the zero-strength iron nanoparticles alone at pH=3. More than 85% of nitrate was restored to ammonium. By increasing the humic acid to the solution, the concentration of ammonium and nitrite increased significantly, which could be due to the oxidation of part of the protein compounds structure of humic acid being in the vicinity of nanoparticles. Nanoparticles Zero Iron (nZVI) not only eliminated nitrate but also removed organic soluble organic matter. Ammonium bands of humic acid are hydrated in the presence of Nanoparticles Zero Iron (nZVI) and part of the ammonium produced at the surface of the oxidation solution. Therefore, with further experiments, it is hoped that the removal of nitrates and soluble organic matter with Nanoparticles Zero Iron (nZVI) from water resources would be possible.