OICC Press Journal of Nanostructure in Chemistry 2193-8865 11 1 (March 2021) 2020 11 21 Desulfurization of gas condensate under visible light using synthesized photocatalysts of Mn/TiO2/MWCNTs and Ni/TiO2/MWCNTs 10.1007/s40097-020-00349-7 EN Ilnaz Raeisi Faculty of Chemistry, Islamic Azad University Tehran North Branch, Tehran, IR Pirouz Derakhshi Faculty of Chemistry, Islamic Azad University Tehran North Branch, Tehran, IR Parviz Aberoomsand Azar Science and Research Branch, Department of Chemistry, Faculty of Science, Islamic Azad University, Tehran, IR Mohammad Saber Tehrani Science and Research Branch, Department of Chemistry, Faculty of Science, Islamic Azad University, Tehran, IR Journal Article 2020 11 21 Abstract In this study, Manganese (Mn) and Nickel (Ni) doped on titanium dioxide (TiO 2 ) were loaded on Multi-Walled Carbon Nanotubes (MWCNTs). These catalysts were characterized by X-ray diffraction (XRD), Fourier Transform Infrared Spectrometer (FTIR), Scanning electron microscope (SEM), Transmission electron microscopy (TEM), X-ray energy dispersive spectrometer/Mapping (EDS/Map), Brunauer, Emmett, Teller (BET)/Barrett, Joyner, Halenda (BJH) and Diffuse Reflectance Spectroscopy (DRS) methods. A batch reactor was designed and photoactivity of these materials prepared under visible light irradiation was tested using dibenzothiophene (DBT). The Response Surface Methodology (RSM) based on Box–Behnken Design (BBD) was used to evaluate parameters including catalyst mass (g), time (h) and dopant percentage (wt%). The best point for maximum degradation efficiency was obtained under optimum conditions for Mn/TiO 2 /MWCNTs and Ni/TiO 2 /MWCNTs catalyst masses of 0.25 and 0.22 (g), time of 5.30 and 4.56 (h), and dopant percentage of 4.22 and 7.82 (wt%) with an efficiency of 92.82 and 98.26%, respectively. Under optimal conditions for the degradation of DBT sulfur, was investigated desulfurization of gas condensate. The highest desulfurization efficiency was obtained by Ni/TiO 2 /MWCNTs catalyst at 89.11%. The results of kinetic studies show that the Blanchard model has the best agreement with the experimental data. Graphic abstract