CoCu-based-ZSM-5 activates PMS for efficient LEV degradation: Dual mechanism degradation dominated by singlet oxygen

Abstract

In this study, a CoCu-based-ZSM-5 (CCM-0.2) material with high stability and excellent reactivity was synthesized to activate PMS for the degradation of levofloxacin (LEV). This material was synthesized by combining Co₃O₄ and CuO nanoparticles with ZSM-5 zeolite through an in-situ synthesis method. The findings demonstrated that the CCM-0.2/PMS system was capable of efficiently degrade LEV in a pH range of 5–9, achieving a degradation efficiency of 96 % within 30 min under optimal conditions. Furthermore, the system exhibited favorable degradation performance for various antibiotics and adaptability to different water quality conditions, maintaining a degradation efficiency of 81 % after five cycles of experiments. Quenching experiments and EPR detection revealed the presence of a radical/non-radical dual degradation mechanism in the CCM-0.2/PMS system, with ¹O₂ being the predominant species. The degradation pathway of LEV and the toxicity of its intermediate products were analyzed using LC-MS and the ECOSAR software.