This monograph provides a comprehensive reference on chlorine-based advanced oxidation processes. It examines the fundamental chemistry of chlorine and the mechanistic pathways governing the degradation of micropollutants in water and wastewater. It also covers the major activation techniques, including photolytic, catalytic, photocatalytic, electrochemical, ultrasonic, and hybrid processes, to elucidate how reactive species are generated and how pollutants are degraded. The book integrates fundamental chemistry, process engineering, and reactor configuration considerations, thereby bridging theoretical concepts with practical water-treatment applications. It further reviews recent experimental advances, highlights the potential of synergistic hybrid systems, and serves as both a scientific and practical guide for researchers, graduate students, and professionals in environmental chemistry, chemical engineering, and water treatment.

·Dr. Slimane Merouani is a Professor of Process Engineering in the Department of Chemical Engineering at Constantine 3 Salah Boubnider University, Algeria. He obtained his Accreditation to Supervise Research (ASR) in Process Engineering in 2015 from Constantine 3 Salah Boubnider University. He received his PhD in Chemical Engineering in 2014 and his Magister (MSc) degree in 2010, both from Badji Mokhtar-Annaba University, Algeria. He also holds a State Engineer Diploma in Chemical Engineering (2006) from Constantine 1 University, Algeria. Prof. Merouani's research focuses primarily on innovative technologies for water and wastewater treatment, with particular emphasis on sonochemistry and advanced oxidation processes (AOPs). He has successfully supervised 10 PhD and 30 MSc theses to completion. He has coordinated numerous national research projects and led editorial activities in the fields of chemical and environmental engineering. Prof. Merouani serves as an Associate Editor for Scientific African (Elsevier) and as an Editorial Board Member of Ultrasonics Sonochemistry (Elsevier). He has also served as Guest Editor for several Special Issues in MDPI journals, including Catalysts, Energies, and Molecules, and regularly reviews manuscripts for more than 40 Q1-ranked journals covering environmental science, process engineering, energy, and materials science. He has authored more than 180 Q1 peer-reviewed articles, edited or co-authored five books, and contributed to approximately 70 book chapters published by major academic publishers, including Elsevier, Springer Nature, Taylor & Francis, and De Gruyter. With more than 6,500 citations and an h-index of 45 (Scopus), he is among the most highly cited researchers in his field in Algeria. Since 2022, he has been continuously listed among the World's Top 2% Scientists, based on the Stanford University ranking. In 2020, he was ranked first nationally during the 44th session of the Algerian National University Commission for full professorship (Order No. 986).