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

An efficient MnCeO_x 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_x was better than MnO_x, CeO₂ and MnO_x + CeO₂. 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_x/persulfate system. Moreover, MnCeO_x/persulfate system showed high efficiency in pH range of 5-9. Mechanism analysis showed that SO₄^- and OH on the surface of the catalyst were the main active species, and O₂^- also played an important role in pollutants degradation. Furthermore, MnCeO_x 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.