TOC removal of diethylene glycol mono-n-hexyl ether synthetic wastewater and 1,4-butanediol diglycidyl ether synthetic wastewater with H₂O₂/UV in a batch reactor

Total organic carbon (TOC) removals of two synthetic wastewaters which contain diethylene glycol mono-n-hexyl ether (DGME) and 1,4-butanediol diglycidyl ether (1,4-BDE) respectively as a main component, have been carried out by using hydrogen peroxide and ultraviolet irradiation (H₂O₂/UV). Experiments were carried out in a batch reactor with a low pressure UV lamp (500 W) irradiating ultraviolet at 254 nm and at 185 nm (5% of energy). The following results were obtained. (1) The complete TOC removals of the two synthetic wastewaters have been obtained. TOC removals of the two synthetic wastewaters are pseudo-first-order processes. (2) The removal rates of TOC of the two synthetic wastewaters were governed by the concentration of hydrogen peroxide added initially and the maximum pseudo-first-order rate constant and the optimum initial hydrogen peroxide concentration existed both in the two synthetic wastewaters. (3) The relation between the initial TOC concentration and the optimum initial hydrogen peroxide concentration exhibited linear in both synthetic wastewaters. The optimum initial hydrogen peroxide concentration in the TOC removal of the 1,4-BDE synthetic wastewater is higher than that of the DGME synthetic wastewater at the given initial TOC concentration. (4) The maximum pseudo-first-order rate constant increases with the decrease in the initial TOC concentration in both synthetic wastewaters. The maximum pseudo-first-order rate constant for the DGME synthetic wastewater is higher than for the 1,4-BDE synthetic wastewater at the given initial TOC concentration. (5) The experimental results agree well with the theoretical consideration which has been previously proposed by authors (Hou et al., 2001c) while hydrogen peroxide concentration and TOC concentration in the wastewater were very high.