Decomposition of chloroform and trichloroethylene in deionized water with the use of low voltage electron beam

Paper presents the experimental setup and the results of the laboratory scale experiment concerning a water purification by electron beam irradiation. The setup was designed to use the circulation water flow in order to control (by the time of circulation) the absorbed dose of radiation. The electron beam was generated in vacuum p=10^-5 Torr, and accelerated using the voltage within the range of V=100-185 kV. Electrons were injected into the water through titanium foil with thickness d=25 μm. The electron beam current was within the range of I=0.5-1.2 mA. Trichloroethylene (TCE) and chloroform water solutions were used in the experiment. Although the initial contents of the compounds were higher than those occurring in real water sources and during drinking water treatment, it has been found that it is possible to decompose both of the chemicals with high efficiency L total decomposition in the case of TCE, and up to 90% of reduction for chloroform- using a relatively low accelerating voltage. The dependencies of the relative contaminant concentration (c=C/C₀, where C is a weight content of compound after electron irradiation, C₀ is an initial concentration of a contaminant) on the time of water circulation, and on the absorbed dose are presented. The results have indicated that the relative removal of TCE and chloroform mainly depends on the absorbed dose of electron radiation