MnCeO with high efficiency and stability for activating persulfate to degrade AO7 and ofloxacin.

An efficient MnCeO composite was successfully synthesized for activation of persulfate to degrade acid orange 7 (AO7) and ofloxacin. Pollutants degradation efficiencies with different catalytic systems were investigated. Results showed the performance of MnCeO was better than MnO CeO and MnO + CeO. Thus, there was a clear synergistic effect (Se) between Mn and Ce in the composite, and the Se was 73.8% for AO7 and 39.6% for ofloxacin. In addition, AO7 removal fitted 1st order reaction while ofloxacin removal fitted 2nd order reaction in MnCeO/persulfate system. Moreover, MnCeO/persulfate system showed high efficiency in pH range of 5-9. Mechanism analysis showed that SO and OH on the surface of the catalyst were the main active species, and O also played an important role in pollutants degradation. Furthermore, MnCeO showed high activity in actual water. Finally, the possible degradation pathway of ofloxacin was proposed according to the high performance liquid chromatography-mass spectrometry result. Overall, this study provides an efficient and stable catalyst to activate persulfate to degrade refractory pollutants.