Effects of UV/H2O2 preoxidation on the aerobic biodegradability of quaternary amine surfactants

Several quaternary amine surfactant solutions were mixed with an equal amount of hydrogen peroxide, adjusted to pH 8 and irradiated at 254 nm at 0.56 W per litre at 22C for up to 2 h. The products of this reaction were assessed for biodegradability by aerobic batch activated sludge bioassays in which DOC concentrations were regularly monitored. Initial attempts to use ozone in the advanced oxidation treatment were abandoned because of foaming. The pretreatment enhanced the biodegradability of alkyldimethylbenzyl ammonium chlorides, but had little beneficial effect on dioctyl-dimethyl ammonium chloride.