Synthesis of MnOx/SBA-15 for Norfloxacin degradation by catalytic ozonation

Abstract

Abstract Norfloxacin, a kind of widely used fluoroquinolone antibiotics, was degraded by MnOx/SBA-15/O3 process. The prepared catalyst possessed a large surface area ranging from 405 to 671 m2 g−1, which was beneficial for surface reaction. The loaded MnOx on SBA-15 successfully increased its the adsorption ability and catalytic activity, and its surface property played an importance role in catalytic process. Under the adopted condition, both O3 and MnOx/SBA-15/O3 systems were effective for Nofloxacin removal. A high mineralization efficiency (54%) was achieved by MnOx/SBA-15/O3 process at 60 min, 1.36 times higher than that of single ozonation process. The protonated surface hydroxyl groups were the main reaction sites and more hydroxyl radicals generation were found after the presence of MnOx/SBA-15. Three kinds of common small molecule acid (oxalic acid, formic acid, acetic acid) were detected, and the concentration of oxalic acid in MnOx/SBA-15/O3 process was lower than that in sole ozonation process because more OH generated in catalytic ozonation. Toxicological tests were also conducted to evaluate their detoxification ability. As the accumulation of transformation products, the toxicity of solution increased at first and reached the highest after 15 min reaction time. And a high detoxification was achieved after 30 min.