ABSTRACT
As advanced oxidation processes (AOPs) continue to enter the commercial market, treatment efficiency becomes an important factor for selecting a process with better cost efficiency. To analyze the cost efficiency, comparisons between selected AOPs have been reported in recent years. A number of variables, including initial conditions, pH, oxidant, and catalyst concentrations, have been analyzed in combination with kinetic parameters of the process. The kinetics of each process are described by the rate constants and/ or the reaction half times. These investigations have been conducted under identical experimental conditions so that treatment efficiency can be compared under the same conditions. In addition, combinations of various AOPs have also been analyzed with respect to cost efficiency. This comparison was carried out by combining various oxidants such as oxygen, ozone, and hydrogen peroxide (H
O
) with catalysts such as ultraviolet (UV), Fe
, and TiO
. In general, synergic effects exist when two oxidation systems were combined. This synergy was reflected in a marked increase in the free-radical reaction pathway. The effect was also observed to increase with the complexity of the oxidation systems used. The only exception arose in the comparison of Fenton’s reagent system with a combined Fenton’s reagent/ozone system, in which case there seems to be interference of ozone with Fenton’s reagent through oxidation of Fe
, which reduces the amount of Fe
to decompose H
O
into hydroxyl radicals.
