DECOMPOSITION OF 2-CHLOROPHENOL IN AQUEOUS SOLUTIONS BY OZONE AND UV/OZONE PROCESSES IN THE PRESENCE OF ALCOHOLIC COMPOUNDS

摘要

The decomposition of 2-chlorophenol in aqueous solution by ozone and UV/ozone process was studied with the presence of various alcoholic compounds: t-butanol, ethanol and Triton X-100. The addition of these alcoholic compounds was found to decrease the surface tension of aqueous solutions and might increase the gas-liquid interfacial area to certain extents for bubbling systems by decreasing the size of gas bubbles. The presence of t-butanol was found to promote the decomposition of 2-chlorophenol for both ozone and UV/ozone processes. However, the addition of ethanol and Triton X-100 decreased the decomposition rates of 2-chlorophenol possibly because these alcoholic compounds were partially decomposed and might serve as scavengers for hydroxyl free radicals, and consequently retarded the decomposition of 2-chlorophenol. The pseudo first-order decomposition rate constant of 2-chlorophenol and formation rate constant of chloride were calculated to describe the temporal behavior of 2-chlorophenol in aqueous solution by ozone and UV/ozone process in the presence of various surfactants.