Many of the drugs used arc not completely metabolized in the human body and with urine and faces arc introduced into the sewage system. Finally, due to their incomplete removal during the conventional wastewater treatment process (CWTP), they can be released into the receiving water. One of the medicaments frequently detected in surface water is diclolcnac. The present study addresses the problem of diclofcnac removal in various aquatic samples using advanced oxidation processes (AOPs). The experiments were performed in distilled water and in biologically treated wastewater. The following AO Ps were applied: Fenlon 's reagent, UVand UV/H2O2-processes. The concentration of diclolcnac in distilled water corresponded to the concentration of this drug in human urine (ca. 20 mg-dm'). The real wastewater samples contained diclofcnac concentrations ranging from 630 to 790 ng-dm-'. The photodcgradation of diclolcnac was carried out in the photorcactor with a medium pressure Hg-vapor lamp (400 W). In the Fcnton's reaction different molar ratiosof H2O2/Fc'' were used. The diclotcnac mineralization (TOC removal) strictly depended on the amount of 1-1,0, applied in the Fcnton's reaction. Diclofcnac was rapidly degraded by direct photolysis (UV) and in UV/H2O2,-process both in distilled water and in wastewater samples. The results proved that the advanced oxidation processes arc cflcctive in diclofcnac removal from aquatic samples. The pseudo first order rate constants It)!' diclolcnac photodcgradation were determined.

Surfactants after their use are discharged into aquatic ecosystems. These compounds may be harmful to fauna and flora in surface waters or can be toxic for microorganisms of the activated sludge or biofilm in WWTP. In order to determine effectiveness of different advanced oxidation processes on the degradation of surfactants, in this study the degradation of anionic surfactants in aqueous solution using photolysis by 254 nm irradiation and by advanced oxidation process in a H2O2/UVC system was investigated. Two representatives of anionic surfactants, linear alkyl benzene sulphonate (LAS-R11–14) and ether carboxylic derivate (EC-R12–14E10) were tested. The influence of pH, initial surfactant concentration and dose of hydrogen peroxide on the degradation was also studied. Results show outstanding effectiveness of the H2O2/UVC system in the removal of surfactant from aqueous solutions.