Photochemistry of Colloids and Surfaces in Natural Waters and Water Treatment

Abstract

Particles in the upper layers of marine and freshwaters and in atmospheric water droplets are exposed to solar radiation and absorb a significant amount of this radiation. Although a large portion of the radiation absorbed by naturally occurring particles is converted into thermal energy, it is now recognized that a wide variety of chemical transformations involving suspended particulate matter are initiated by absorption of sunlight (Zafiriou et al., 1984; Zepp and Wolfe, 1987). While abiotic heterogeneous photochemical transformations involving living organisms and particulate organic materials have been reported (Zepp and Wolfe, 1987), photoprocesses involving particles containing transition metal ions are particularly numerous and are the focus of discussion in this chapter.