中文摘要：

采用溶胶凝胶法制备了一系列不同TiO2含量的TiO2-Al2O3复合载体,并通过浸渍法制备了NiO/TiO2-Al2O3催化剂。分别考察了不同TiO2含量的NiO/TiO2-Al2O3催化剂及反应温度对CO甲烷化催化性能的影响。实验结果表明,当复合载体中TiO2质量分数为30%,反应温度为350～450℃时,催化剂催化活性较高。利用N2吸附-脱附（BET）、X射线衍射（XRD）及H2程序升温还原（H2-TPR）等手段对催化剂物化性能进行了表征。结果表明,加入适量的TiO2能抑制镍铝尖晶石NiAl2O4物种的生成,改善NiO的表面分散性能,避免大晶粒NiO的形成,也改善了催化剂的还原性能,从而提高催化剂的CO甲烷化活性。

英文摘要：

A series of TiO2-Al2O3 composite supports with different TiO2 contents were prepared by sol-gel method and then supported nickel catalysts（NiO/TiO2-Al2O3） were obtained by impregnation with NiO/TiO2-Al2O3 as the supports.The effects of TiO2 promoter content and reaction temperature on the performance of TiO2-Al2O3 catalysts in CO methanation were investigated.The results showed that the nickel catalyst supported on the TiO2-Al2O3 composite containing 30 % TiO2 exhibits the highest activity for CO methanation under a temperature from 350 to 450℃.BET,XRD and H2-TPR characterization results indicated that the addition of TiO2 promoter can restrain the formation of Ni/Al2O4,improve the dispersion of NiO,avoid the formation of large NiO granules,and make NiO reduction easier,which can then enhance the activity of the nickel catalysts in CO methanation.