en عمومى General مقاله اصیل Original Article <div style="text-align: justify;">Background: The widespread presence of organic dyes in the various industries&rsquo; effluent such as paper, textile, and clothing has led to significant environmental pollution. Titanium oxide (TiO2) nanoparticles immobilized on zeolite (ZSM-5) were investigated under UV light for activation of peroxymonosulfate (PMS) for photocatalytic degradation of Orange II (OII) dye in aqueous solutions.<br> Methods: In this study, the photocatalyst used was prepared by immobilizing different amounts of TiO2 nanoparticles on ZSM-5. Characterization analyses including X-ray diffractometer (XRD), Fourier transform infrared (FTIR), BET, scanning electron microscope (SEM), and energy dispersive X-ray spectroscopy (EDS) were performed on the synthesized samples. Then, the effect of various parameters, such as TiO2 nanoparticles loading onto the ZSM- 5, pH, contact time, dye concentration, and TiO2/ZSM-5 dosage, is investigated for the removal of OII as a model molecule under the UV irradiation with 15 W power.<br> Results: The highest removal percentage of OII dye (97.44%) was obtained in the optimal operating conditions of pH = 3, the initial dye concentration = 5 ppm, amount of TiO2/ZSM-5 = 10 mg/L, amount of PMS = 50 mg/L, and reaction time = 120 minutes. The Langmuir&ndash;Hinshelwood kinetics model fitted with the experimental data.<br> Conclusion: The obtained results of this research showed that PMS can be used as a suitable oxidant activated with ZSM-5/TiO2 nanocomposite in OII degradation in different water environments, by optimizing the effective operating factors.</div> Coloring agents, Titanium dioxide, Peroxymonosulfate, Textiles, ZSM-5 zeolite 419 428 http://ehemj.com/browse.php?a_code=A-10-1-315&slc_lang=en&sid=1 Parisa Nasrollahi parisa.nas@gmail.com 100319475328460013956 0009-0007-5893-9167 No Department of Chemical Engineering, Ilam University, Ilam, Iran Seyyed Abbas Mirzaee mirzaee.seyyed@gmail.com 100319475328460013957 100319475328460013957 No Health and Environment Research Center, Ilam University of Medical Sciences, Ilam, Iran Zeinab Gholami gholami-z@medilam.ac.ir 100319475328460013958 0009-0004-9643-0378 No Health and Environment Research Center, Ilam University of Medical Sciences, Ilam, Iran Mohsen Mansouri mansouri2010@yahoo. com 100319475328460013959 100319475328460013959 No Department of Chemical Engineering, Ilam University, Ilam, Iran Zahra Noorimotlagh Noorimotlagh.Zahra@ gmail.com 100319475328460013960 100319475328460013960 Yes Corresponding author: Health and Environment Research Center, Ilam University of Medical Sciences, Ilam, Iran