Decomposition of Ethylene Glycol by the Combined Use of Ozone Oxidation Method and Electrolytic Method

Abstract

Decomposition of ethylene glycol by the combined use of an ozone oxidation method and an electrolytic one was studied by changing the concentration of ozone in th e feed gas, the current density, the quantity of NaCl and the concentration of ethylene glycol. The order of the reaction with respect to ethylene glycol was O.8 and the rate constant increased with an increase of the concentration of ozone in the feed gas. Glycolald ehyde, glyoxal, glyoxylic acid and formaldehyde were detected as decomposition products, and the removal of total organic carbon (TOC), which was not attained by eithers of the two methods, was attained. This effect is considered to be caused by active radicals whi ch are formed during the course of this reaction. The decomposition route is estimate d as follows. From this scheme and the fact that a considerable amount of formaldehyde produced, is likely that the TOC removal via formic acid is important as well as that via oxalic acid. The TOC removal was remarkably affected by the concentration of ethylene glycol in addition to the conditions of ozone oxidation and electrolysis method.