Controllable preparation of MnCo2O4 spinel and catalytic persulfate activation in organic wastewater treatment: Experimental and immobilized evaluation

Abstract

Transitional metal oxides are excellent candidates as heterogeneous catalysts for activating persulfate towards organics degradation. In this study, MnCo₂O₄ spinel was successfully prepared using a solvent-free molten method. The catalytic performance was systematically investigated and MnCo₂O₄ powder catalyst was successfully immobilized on polyurethane (PU) membrane through electrospinning to assess its application potential. The results showed that peroxymonosulfate (0.1 ​g ​L⁻¹) activated by MnCo₂O₄ (0.1 ​g ​L⁻¹) reached 99.92 ​% degradation in 10 ​min when treating 0.04 ​g ​L⁻¹ rhodamine B as target pollutant. The abundant oxygen vacancies formation, synergistic effect of Co and Mn ions and high electron transfer mobility are contributing to production of reactive oxygen species. Combining with quenching experiment and time-resolved EPR, the contribution of various active species was proposed, of which ¹O₂ exhibited the dominant role. The flowing reaction run by the MnCo₂O₄-PU membrane activating PMS exhibited universal degradation on different target pollutants.