Ce3+ triggers fenton-like processes in neutral solutions for effective catechol degradation

Classical Fenton and Fenton-like processes destruct organic pollutants in water non-selectively to complete mineralization. However, the usage of classical Fenton or Fenton-like processes is often limited due to the narrow operational pH window, sludge accumulation, inefficient H2O2 and efficiency decline. To overcome these constraints, in this study, we used a homogeneous Fe3+-Ce3+-H2O2 Fenton-like process to degrade catechol at different experimental conditions. At pH 7, almost 97% of 10 mM catechol can be destructed within 60 min while the degradation by Classical Fenton or Fe3+-H2O2 Fenton-like process only 36.2% and 23.7%. The resultant solution after the degradation contains only traces of cerium ions. The sludge created by the process was extensively characterized by FTIR and XPS spectroscopy to elucidate the fate of cerium ions. Electron spin resonance (ESR) data confirmed •OH as the major free radical in Fe3+-Ce3+-H2O2 process. Our Fenton-like process widens the optimal pH values to neutral condition.