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以铈锆固溶体(Ce0.5Zr0.5O2)修饰的高比表面积SiC为载体,采用两步浸渍法制备了Ni、Fe和Co基催化剂,研究了其在煤层气催化燃烧脱氧中的催化活性和稳定性.利用X射线衍射(XRD)、X射线光电子能谱(XPS)、电感耦合等离子体质谱(ICP-MS)、高分辨透射电子显微镜(HRTEM)、比表面积(BET)、热重分析(TGA)和H2程序升温还原(H2-TPR)对催化剂进行了表征.分析结果表明,Ni、Fe和Co部分进入Ce0.5Zr0.5O2固溶体晶格内部,导致催化剂体相形成更多的缺陷;同时Ce0.5Zr0.5O2固溶体有助于加速金属氧化物和金属之间氧化还原过程的进行,促进了氧吸附、传输和对甲烷的活化.另外,SiC和Ce0.5Zr0.5O2固熔体良好的抗积碳性能,有效避免了催化剂在富甲烷反应气氛中因积碳而失活,从而使三种催化剂均具有优良的催化燃烧脱氧活性和稳定性.其中,Co/Ce0.5Zr0.5O2/SiC活性最高,可在320℃活化催化甲烷,并在410℃实现完全脱氧.
Ni, Fe and Co based catalysts with high surface area SiC modified by cerium zirconium solid solution (Ce0.5Zr0.5O2) were prepared by two-step impregnation method, and their catalytic activity and stability in catalytic combustion and deoxygenation of coalbed methane XRD, XPS, ICP-MS, HRTEM, BET, TGA (thermal gravimetric analysis) ) And H2 temperature-programmed reduction (H2-TPR) were used to characterize the catalyst. The results show that Ni, Fe and Co partially enter the lattice of Ce0.5Zr0.5O2 solid solution, resulting in more defects in the catalyst bulk. .5Zr0.5O2 solid solution helps accelerate the redox process between the metal oxide and metal, and promote oxygen adsorption, transport and activation of methane.In addition, SiC and Ce0.5Zr0.5O2 solid solution good anti-product Which can effectively deactivate the catalyst due to carbon deposition in a methane-rich reaction atmosphere, so that all three catalysts have excellent catalytic combustion deoxygenation activity and stability. Among them, the activity of Co / Ce0.5Zr0.5O2 / SiC is the highest , Methane can be activated at 320 ° C and finished at 410 ° C Deoxy.