Solar disinfection is an augmentable, in situ-generated photo-Fenton reaction—Part 2: A review of the applications for drinking water and wastewater disinfection

This is the second part of a comprehensive review article about photo-Fenton reaction at near-neutralpH used for water and wastewater disinfection. In this part, a critical revision of the fundamental physical,chemical and biological parameters affecting the photo-catalytic process efficiency are discussed. Theeffects of the chemical aspects, considered either as facilitators or competitors of photo-Fenton are deeplyanalyzed, with special focus on organic matter and its effect over bacterial inactivation. The role of solubilizediron and the biological nature of different pathogens are deeply assessed according to reportedexperimental data. Water temperature, turbidity, and radiation parameters like solar UV energy, lighscattering and absorption during photo-Fenton are pictured in terms of treatment efficiency and suitablereactor design. Recent unconventional photo-Fenton strategies using iron chelates, iron oxides (includingzero valent iron) and iron-based materials are also highlighted as new approaches to this process. Finally,the existing pilot scale studies in real conditions using photo-Fenton at near-neutral pH are revised, whilealternative options and further research for real implementation are proposed.