چكيده به لاتين
Recently, the importance of environmental issues and air pollution due to sulfur compounds in transport fuels and approval of strict environmental regulation to determine the maximum amount of sulfur in fuels were attracted researchers to find alternative desulfurization methods of petroleum compounds. Therefore, oxidative desulfurization processes are known as a novel, complementary and alternative method to hydrodesulfurization process. In this study, titanium nanostructured catalysts based on activated carbon have been utilized to improve the catalytic properties and characteristics, including the specific surface area and surface chemistry of the catalyst, for use in oxidative desulfurization process. The TiO2/AC nanostrucered catalyst was synthesis by the simple wet impregnation method with Activated carbon and Tert-buthyl orthotitanate (TBOT) as taitania precursor. Properties and structure of catalytic samples using Nitrogen adsorption and desorption analyzes (N2 adsorption-desorption), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), spectroscopy X-ray energy diffraction (EDX), Raman spectroscopy were examined. Oxidative desulfurization process was conducted in a two-port batch reactor using Heating water reflux for cooling, with 3gr fuel model containing N-dodecane solvent and 500 ppm sulfur of dibenzothiophene with Tert-butyl hydroperoxide (TBHP) with molar ratio O/S=5 and in the presence of 0.03gr of catalyst at 80℃ temperature and 1atm pressure. DBT conversion rate was measured using gas chromatography.The effect of various parameters such as TiO2 loading rate, temperature, oxidizing concentration, stability, and adding competitive compounds in the final desulfurization product were investigated.The optimum 20TiO2/AC7ox catalyst with 7 hours oxidized carbon support by 68% nitric acid was selected. In addition the optimum temperature was 80°C, and the optimal O/S molar ratio was selected 5. The 20TiO2/AC7ox catalyst converted the complete removal of the Dibenzothiophene sulfur compound to over 98% in less than 10 minutes.
