Effect of ozone oxidation on the molecular and kinetic properties of effluent organic matter

The effect of ozone oxidation on the second order reaction rate constant between effluent organic matter (EfOM) and hydroxyl radical (·OH), k _OH-EfOM, has been evaluated. Previously, this rate constant was measured for EfOM samples collected from five geographically distributed wastewater treatment plants. The k_OH-EfOM values ranged from 2.70 - 12.1 x 10⁸ Mc^-1 s^-1. One additional EfOM sample collected during this study was pre- oxidized using different ozone dosages. While oxidation by ozone resulted in considerable change to the physico- chemical properties of the EfOM the reaction rate constant (measured initially as (4.38 ± 0.06) x 10⁸ M^-1 s^-1) did not significantly change. This indicates that the reaction rate constant could be assumed to be constant during the application and modeling of advanced oxidation processes for water reuse applications.