Abstract
The study concerns the photodecomposition of volatile chlorohydrocarbons (VCs) with hydroxyl radical which derives from the photo-dissociation of Fe (III)-monohydroxy complex at acidic pH.
The initial decomposition rate of chloroform (CF) with irradiation of a 500 W high-pressure mercury lamp at pH : 3.0 was smaller than those of trichloroethylene (TCE) and tetrachloroethylene (PCE). However, the conversion of organic chlorine of CF to chloride ion was larger than those of TCE and PCE. The generation rates of ferrous ion differed greatly, depending upon chlorohydrocarbons.
The initial decomposition rates of PCE with irradiation of monochromatic light (313nm) were measured at pH : 3.0. The results were in good agreement with the kinetic model that assumed the steady-state concentration of hydroxyl radicals. The intermediate identified in the photodecomposition of PCE other than chloride ion was trichloroacetic acid (TCAA).
