Advances in the Degradation of Emerging Contaminants by Persulfate Oxidation Technology

The activation of persulfate has received considerable attention for its potential application in the removal of pollutants. In recent years, various technologies have been developed to catalyze its activity, which can be classified into two main methods: homogeneous and non-homogeneous activation. Homogeneous activation methods encompass thermal activation, photoactivation, ultrasonic activation, electrical activation, microwave activation, and transition metal ion activation. What is more, non-homogeneous activation methods include activation through metal-based nanomaterials, MOF material activation, single-atom catalysts, piezoelectric effect activation, and carbon activation. In this review, it presents a comprehensive overview about the advantages and disadvantages of these activation methods, as well as the main reaction mechanisms. Additionally, chemical identification methods such as quenching, chemical probes, and isotope techniques are discussed. Furthermore, the article explores two characterization methods, electron paramagnetic resonance, in situ Fourier transform infrared spectroscopy and Raman spectroscopy, and mass spectrometry, and their application in experimental studies. Finally, the current limitations of each technique and future research directions are discussed and prospected. This article aims to provide valuable insights into the various activation methods of persulfate and their applications in the field of environmental science and technology.