Photocatalytic decontamination and disinfection of water with solar collectors

In recent years, there has been a tremendous amount of research and development in the area of photocatalysis, a process included in a special class of oxidation techniques defined as advanced oxidation processes (AOPs), all characterized by the same chemical feature, production of (OH)-O-center dot radicals. This paper reviews the use of sunlight to produce the (OH)-O-center dot radicals. The systems necessary for performing solar photocatalysis are described. The paper also summarizes most of the research related to solar photocatalytic degradation of water contaminants carried out during recent years, and how it could significantly contribute to the treatment of very persistent toxic compounds. Various solar reactors for photocatalytic water treatment based mainly on non-concentrating collectors erected during the last few years are also described in detail in this review, as well as the use of the solar photocatalytic processes to inactivate microorganisms present in water, placing special emphasis on some experimental systems erected to optimize this disinfecting technique. (c) 2007 Elsevier B.V. All rights reserved.