Predicting Fenton-driven degradation using contaminant analog

The reaction of hydrogen peroxide (H{sub 2}O{sub 2}) and Fe(II) (Fenton's reaction) generates hydroxyl radicals ({center_dot}OH) that can be used to oxidize contaminants in soils and aquifers. In such environments, several factors can limit the effectiveness of chemical oxidation, including reactions involving H{sub 2}O{sub 2} that do not yield {center_dot}OH, {center_dot}OH reactions with nontargeted chemicals, and insufficient iron in the soil or aquifer. Consequently, site-specific studies may be necessary to evaluate the feasibility of chemical oxidation using H{sub 2}O{sub 2}. Here, the degradation of a contaminant analog, {alpha}-(4-pyridyl-1-oxide) N-tert-butylnitrone (4POBN), was used to estimate {center_dot}OH concentration and simplify testing procedures. A kinetic model was developed, calibrated using 4POBN degradation kinetics, and used to predict the disappearance of 2-chlorophenol (2CP), a representative target. Good agreement between predicted (Y) and measured (X) values for 2CP (Y = 0.95 X) suggests that the kinetics of analog degradation can be used to predict the degradation rate of compounds for which the rate constant for reaction with {center_dot}OH is known.