Abstract: | Aromatic sulfonates can be found in drinking water. Thus, they must have passed water treatment and survived ozonation. Degradation of aromatic sulfonates can be achieved by the UV/H2O2‐process. Since drinking water is often treated with chlorine as a disinfectant, the formation of disinfection by‐products has to be considered. Therefore, the production of AOX (on activated carbon adsorbable organic halogens) after chlorination of the sulfonates with and without preoxidation was investigated. Instead of the analysis of the individual degradation products, the determination of the sum parameter AOX was used as a fast screening method. The investigated sulfonates were: anthraquinone‐2‐sulfonate, naphthalene‐2‐sulfonate, 2‐aminonaphthalene‐1‐sulfonate, and 4,4′‐diaminostilbene‐2,2′‐disulfonate. All sulfonates containing amino groups showed high potentials of AOX formation. The preoxidation with ozone increased the potentials of AOX formation in general. Treating the sulfonates by using the UV/H2O2‐process, the formation potentials run to zero after going through a maximum value. |