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The recirculating split-flow batch reactor with a cell divided into anolyte and catholyte compartments for oxidation mixture of cytostatic drugs (CD) was tested. In this study, kinetics and mechanisms of electrochemical oxidization of two mixtures: 5-FU/CP and IF/CP were investigated. The order of the CD degradation rate in single drug solutions and in mixtures was found to be 5-FU < CP < IF. In the 5-FU/CP mixture, kapp of 5-FU increased, while kapp of CP decreased comparing to the single drug solutions. No effect on the degradation rate was found in the CP/IF mixture. The presence of a second drug in the 5-FU/CP mixture significantly altered mineralization and nitrogen removal efficiency, while these processes were inhibited in IF/CP. The experiments in the different electrolytes showed that •OH and sulphate active species can participate in the drug's degradation. The kapp of the drugs was accelerated by the presence of Cl− ions in the solution. Chlorine active species played the main role in the production of gaseous nitrogen products and increased the mineralisation. Good results were obtained for the degradation and mineralisation processes in mixtures of drugs in municipal wastewater-treated effluent, which is beneficial from the technological and practical point of view. [ABSTRACT FROM AUTHOR]

• BiOCl1.3Br0.7 effectively removed IMA and 5-FU singly and in their mixture. • Inorganic anions has significant effect on IMA adsorption at BiOCl1.3Br0.7. • IMA and inorganic anions significantly inhibited the 5-FU removal. • Holes mainly participated in drugs degradation, but not its mineralization. • Toxicity decreased after photodegradation of IMA and 5-FU singly and in mixture. The photocatalytic activity of series of BiOCl n Br m photocatalysts toward degradation and mineralization of the cytostatic drugs 5-fluorouracil (5-FU) and imatinib mesylate (IMA) both singly and in their mixture under simulated solar and visible light irradiation has been investigated. Screening test revealed that among BiOCl n Br m photocatalysts synthesized by a solvothermal method, the one with molar 1.3Cl/0.7Br ratio was the most efficient in 5-FU removal under UV–Vis irradiation. The dose 200 mg L−1 and 6.3 pH were optimal to effective removal of 5-FU. The BiOCl1.3Br0.7 was successfully used to 5-FU and IMA removal singly and in their mixture under simulated solar and visible light irradiation. Scavenging experiments showed that h+ and •O 2 − were the major oxidative species participated in both drugs degradation. In presence of IMA, 5-FU removal was significantly depressed. In singly drug solutions and in the mixture of drugs, the presence of inorganic ions such as Cl−, SO 4 2−, and NO 3 − significantly hindered 5-FU photocatalytic degradation, and increased the adsorption of IMA onto the photocatalyst surface in dark phase. The HCO 3 − anion, Fe3+ and Ag+ cations accelerated the 5-FU removal, while Ca2+ showed no impact on the process. The transformation products of 5-FU and IMA were identified by LC-MS revealing that hydroxylation and oxidation were the main transformation pathways, under the all studied systems. Some of intermediates were indicated for the first time in heterogeneous photocatalysis. The defluorination of 5-FU by the reaction with photogenerated e− was also possible. Furthermore, the alga toxicity assay was investigated using Chlorella vulgaris. A reduction of toxicity in effluents after photocatalytic degradation of both drugs singly and in their mixture was observed. [ABSTRACT FROM AUTHOR]