Preface

Nowadays, environmental pollution in the process of industrialization has become a global environmental crisis threatening human beings and aquatic life. To achieve environmental remediation, advanced oxidation processes (AOPs) with highly reactive oxidative species (ROS) have been applied to degrade micro-pollutants into carbon dioxide, harmless inorganic salts, and water. With the aim to overcome the technical limitations of H₂O₂, the persulfates of peroxodisulfate (PDS, known for producing SO₄˙⁻) and peroxymonosulfate (PMS, known for producing both SO₄˙⁻ and HO˙) as some of the emerging ROS precursors in AOPs, have attracted more and more attention in environmental remediation. As a result, the fundamentals, applications, advanced activation methods, and coupled catalytic technologies of persulfate-based AOPs for environmental remediation have been widely researched with a surge in scientific publications.

This book contains 12 chapters, deeply elaborating and discussing the development of persulfate-based AOPs in environmental remediation from the three aspects of activation technology, advanced activator, and reaction mechanism and application. From the perspective of persulfate activation technology, this book provides a specific and in-depth introduction on general methods (Chapter 1), photo-activated (Chapter 2), electrochemistry-activated (Chapter 3), and the ROS chemistry in catalytically activated PDS (Chapter 4). Then it covers, metal/metal oxide-activated (Chapter 5) and metal-free carbocatalysis-activated (Chapter 6) persulfate-based AOPs to enumerate the advanced persulfate-activated materials to improve the generation of ROS for the removal of micro-pollutants. From the perspective of reaction mechanism, Chapter 7 manifests the reaction mechanism at the electronic and atomic level based on theoretical chemistry studies, which is helpful to guide and estimate the performance and mechanism on the persulfate-based AOPs for environmental remediation. From the perspective of applications, Chapters 8–12 provide a deep insight into the application of persulfate-based AOPs in water and wastewater disinfection (Chapter 8), inactivation of pathogenic microorganisms (Chapter 9), landfill leachate treatment (Chapter 10), soil remediation of contaminated sites (Chapter 11), and other applications (Chapter 12).

With the rapid development of persulfate-based AOPs as a mature research topic, comprehensive applications have appeared in environmental remediation including certain areas of water and wastewater treatment, landfill leachate treatment, soil remediation and air purification. For future development, a clear understanding of the chemical reaction in persulfate-based AOPs becomes more important. Depending on the pathway of persulfate activation and the water matrix, other weaker and more selective oxidants, such as singlet oxygen (¹O₂), halogen radicals, and high-valent metals can also be formed. Persulfate-based AOPs provide the opportunity to adjust certain oxidants and oxidation mechanisms according to the persulfate activation method and water matrix. Out of the consideration for environmental friendliness, the selection of persulfate-based AOPs should be based on a toxicity assessment of degradation intermediates by theoretical and experimental analysis.

This book is mainly based on the relevant studies and reports of environmental remediation by persulfate-based AOPs in recent years. We hope that this book will enable readers to understand the research progress and future development direction of persulfate-based AOPs, and arouse readers’ interest and discussion, especially the researchers, students, and experts who are interested in the research of persulfate-based AOPs.

Mingshan Zhu

Chun Zhao

Zhenfeng Bian