Systematically studied the oxidation of enrofloxacin (ENR) in a nanoscale zero-valent copper (nZVC)-activated molecular oxygen system. The results show that nanoscale copper powder has a higher surface area than microscale copper powder, non-porous structure, and rough surface and exists in form of agglomerates. Nanoscale ZVC shows a superior activated performance toward molecular oxygen compared with microscale ZVC, which is due to its larger specific area and the fact that it corrodes easier. The H2O2 generated from the activation of molecular oxygen and the Cu+ released from surface corrosion form a novel Fenton-like system in which hydroxyl radicals are continuously produced, resulting in high-efficiency removal of ENR from water. The superoxide radicals produced during the reaction promote the reduction of Cu2+ to Cu+, thus speeding up the removal of ENR. The reaction conditions have a certain effect on the ENR degradation in nZVC-activated molecular oxygen systems. A higher nZVC dosage, lower ENR concentration, higher reaction temperature, and strong acidic conditions are favorable for the ENR removal.
Keywords: degradation; enrofloxacin(ENR); hydroxyl radicals; molecular oxygen; nanoscale zero-valent copper(nZVC).