Study on ammonia oxidation using nano-FeCu is very limited. A comparison of the various features that are related to each considered material was also made. For the other zero-valent metals tested, a detailed description of the works present in the literature was carried out. Finally, the different materials that were employed as support for the nanoparticles were examined. For each Fe 0 form, the effects of the initial pH, the presence or absence of dissolved oxygen, the initial nitrate concentration, the temperature, and the dissolved ions on the nitrate removal process were separately evaluated. The studies that dealt with zero-valent iron were discussed by considering microscopic (mZVI) and nanoscopic (nZVI) forms. Therefore, in the present review, the most recent papers concerning the use of zero-valent materials for chemical denitrification were analysed. To the best of our knowledge, a comprehensive work on the use of the various zero-valent materials that are employed for the removal of nitrate is still missing. Aluminium (ZVA), magnesium (ZVM), copper (ZVC), and zinc (ZVZ) are alternative zero-valent metals that are studied for the removal of nitrate from water as well as from aqueous solutions. The most utilized material for chemical denitrification is zero-valent iron (ZVI). Compared to traditional methods, the chemical denitrification through zero-valent metals offers various advantages, such as lower costs, simplicity of management, and high efficiencies. Various conventional techniques can be applied for the removal of nitrate from water and wastewater, such as biological denitrification, ion exchange, nanofiltration, and reverse osmosis. Nitrate is a widespread water contaminant that can pose environmental and health risks.

Chemical review core shell structure