Radiation-induced degradation of water pollutants - state of the art

The radiation-induced decomposition of biological resistant pollutants in drinking as well as in wastewater is briefly reviewed. First, some important units, definitions etc., radiation sources, as well as dose-depth curves in water as functions of the electron energy and 60Co-γ-rays are mentioned. Following is a schematical presentation of water radiolysis and of characteristics of primary free radicals. Then the degradation of some aliphatic and aromatic chlorinated compounds in the presence of air is presented. Some spectroscopic and kinetic data of transients resulting from chlorinated phenols are also quoted in order to illustrate and to explain the rather complicated degradation mechanisms. In this respect the synergistic effect of radiation and oxygen as well as that of ozone is also discussed. Finally, a scheme for technical application of high energy electron beam is presented. (author)