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چکیده
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The development of practical processes that are capable of converting greenhouse gases into valuable fuels and chemicals, is a major scientific challenge among researchers in the process and environmental fields. In this regard, dry reforming of methane is a very good option which produces synthesis gas as a feedstock for some industries by using two greenhouse gases, CH4 and CO2. Noble metal supported catalysts have excellent performance to advance this reaction, which are mainly replaced by transition metals such as Ni due to the scarcity and high prices. Deactivation due to coke deposition and active sites sintering are major problems in using this catalysts in the dry reforming of methane reaction. In this study, a purely ordered mesoporous silica FSM-16 sample as well as six modified Al-FSM-16 and Ti-FSM-16 samples with the Si/Al and Si/Ti molar ratio equal to 100, 50 and 20, were prepared by template assisted self-assembly of kanemite, which is synthesized from reaction of NaOH and SiO2. Then, Ni/FSM-16, Ni/Al-FSM-16 and Ni/Ti-FSM-16 catalysts were prepared with 10 wt.% nickel by double-solvent impregnation method. Samples were characterized by diffraction X-ray, N2 adsorption/desorption, scanning electron miscroscopy, thermal gravimetric analysis and energy dispersive X-ray spectroscopy. The evaluation of the catalytic performance of the samples in the DRM process at the temperature range of 750-850 ?C showed that the best conditions for the DRM reaction are the feed ratio of CH4: CO2= 1:1 and the flow rate of 60 ml/min. In these conditions, Ni/Al50-FSM-16 catalyst has the best catalytic performance with XCH4 = 84% and XCO2 = 80% at 850 ?C. Subsequently, the Ni/Ti100FSM-16 catalyst with XCH4 = 71% and XCO2 = 69% at the same temperature exhibited the best performance among the catalysts containing Ti metal. The results show that the incorporation of metals (Al and Ti) into silicate frameworks of the catalyst's support increases its catalytic activity significa
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