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percentages. Among which, 0.5 M ZnO-FA-Sep competes with the 0.5 M ZnO-FA within 10min irradiation. The slight difference in the degradation and decolorization percentages may be due the smaller variations in theZnO crystalline sizes, BETareas andpore volumes (DZnO=8.12nm,BET=60m 2g 1,Vpore=0.122cm 3g 1 for0.5MZnO-FAandDZnO=11.6nm, BET = 50.2m2 g 1, Vpore = 0.097 cm 3 g 1 for 0.5MZnO) [12]. Although FA-Sep has amore complex structure than theFAalone,ZnOnanoparticles in the ternary systemare locatedon the external surfaces of both FAand Sep showing no preference to any of theseminerals as detected in the SEM images.Moreover, FAaswell as Sep crystals do not agglomerate in the ternary composite owing to theirmorphological differences in shape and sizes. This creates uniqueness for0.5MZnO-FA-SepandenhancesdispersionofZnOnanoparticles. 4.3.3.Reusability Furthermore, to investigate the photocatalytic stability of 0.5MZnO-FA-Sep, cyclic experi- mentsarecarriedoutunderthesameexperimentalconditions (Figure4D).Foreachrun,0.5M ZnO-FA-Sepis filtrated,washedandcalcinedat500 Cfor2h.After fourcycles, thepercentage ofMOremaining in solution is found to increase onlyapproximately 2% (from15 to 17% for decolorization process) and 3% (from 12 to 15% for degradation process). The slight incre- ments in the percentages can be attributed to the catalyst loss during each collection and rinsingsteps. 5.Conclusions Aternary-supported catalyst hasbeenpreparedandcharacterizedbyXRD,BET, SEM(EDX), XPSandDRUVtechniques.ZnOnanoparticles are found tobedispersedonbothFAandSep minerals. Supported catalysts exhibit higher surface areas andporevolumes thanFA-Sep, FA and 0.25 M ZnO DZnO sizes do not exhibit significant differences depending on the ZnO loading concentrations. EDX, mapping and XPS analysis evidence the existence of ZnO nanoparticles. Moreover, supported catalysts exhibit an absorption edge similar to 0.25 M ZnO with a slight blue shift. High dark adsorption capacities of the supported catalysts improve theirphotocatalytic activities,which further enhancedwith theZnOloadingconcen- tration. The existence of both FA and Sep with different shapes and sizes decrease their agglomerationandexposemoreof their surfaces for theadsorptionofZnOnanoparticles. Future studies will focus on the development of new composites and their applications in environmental issues. Acknowledgements This studywas supportedbyBoğaziçiUniversityResearchFoundation (ProjectNo. 17B05P4/ 13021). Advanced Chemical Kinetics160