| Due to the good physical, chemical and electrical properties, SiC has great potentials in the fields of machinery manufacture, industrial catalysis, semi-conductor device, etc. several methods have been employed to synthesize SiC with various morphologies. In this thesis, SiC with specific surface area higher than 100 m2g-1 was prepared by controlling the calcination process via carbothermal reduction route. SiC with morphologies of honeycomb, nanowire, nano-rod, nano-plate and microsphere were obtained by adjusting the catalyst amounts. With SiC as catalyst carrier and Ni as active sites, highly catalytic activity was achieved in the reforming of CH4-CO2 reaction. Moreover, coke resistance of the catalyst was improved,. The prepared samples were characterized by X-ray diffraction (XRD), N2 adsorption-desorption, Energy Dispersive Spectrometer (EDS), X-ray photoelectron spectroscopy (XPS), Field emission-Scanning electron microscopy (FE-SEM) and Transmission Electron Microscope (TEM).Based on the orthogonal experimental results, the best conditions for preparing SiC with high specific surface area is:the composite material of SiO2/C was calcined at 1300℃for 1-3 hours to get SiC with surface area higher than 130 m2/g.The controlling of SiC morphologies were achieved by chaning the dopping amounts of CeO2 catalyst the reaction temperature and reaction time. Furthermore, the growth mechanism of SiC nanowire during carbothermal reduction process was preliminary explored.Ni/CeO2/SiC catalyst was prepared by doping Ni onto the composite of CeO1/SiC. High catalytic activity with the CH4 conversion of 90% and products selectivity of 100%, was revealed for CO2 reforming with methano to syngas on Ni/CeO2/SiC. With a certain amount of catalytic promoter CeO2 been added, the coke resistance was significantly improved. Though excess of catalytic promoter could further improve the coke resistance capability, the catalytic efficiency would be decreased. |
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