Characterization of Oxidation processes: ozonation and the AOP O3/H2O2

Abstract

The influence of water quality parameters (dissolved organic matter and alkalinity) on the efficiency of the ozone/hydrogen peroxide (O3/H2O2) advanced oxidation process (AOP) relative to the corresponding conventional ozonation process was investigated. In natural waters with a high natural organic matter content (≥3 mg/L), O3 decomposition is controlled by radical‐type chain reactions. Thus, the overall OH radical oxidation capacity is nearly independent if conventional ozonation is replaced by O3/H2O2 AOP. In contrast, when the organic matter content in the natural water is low (≤1 mg/L), the addition of H2O2 considerably enhances the oxidation capacity by OH radicals. A constant ratio between the OH radical and O3 concentration (Rct) was found during both treatments, making it possible to predict the oxidation of micropollutants with O3 and OH radicals if the rate constants of both oxidants are known. The oxidation of atrazine during ozonation and the combined process O3/H2O2 could be accurately predicted in natural waters.