复合载体镍基催化剂的一氧化碳甲烷化反应研究

Study of Ni/Al2O3-TiO2 Catalysts for CO Methanation

关键词:  一氧化碳  甲烷化  镍催化剂  铝钛复合载体

Key words:  carbon monoxide  methanation  supported nickel catalysts  Al-Ti supports

摘要:

本文分别以沉淀法和共沉淀法制备三氧化二铝载体及不同铝钛比的复合载体;用浸渍法负载活性组分镍,再通过一氧化碳甲烷化反应考察其催化性能。结果 表明,Ni的最佳担载量是15%(w),高TiO2含量复合载体制备的催化剂的活性和选择性最佳,其中催化剂15%Ni/60%Al2O3-40%TiO2的CO转化率在90%以上,CH4选择性达到100%。在320℃～440℃范围内,催化剂活性随温度升高而提高。在空速为5 000h-1～15 000h-1范围内,随着空速的增大催化剂活性降低。

Abstract:

Al2O3 support and different Al/Ti ratio mixed oxides supports were prepared by precipitation method and co-precipitation method.Ni/Al2O3 and Ni/Al2O3-TiO2 catalysts were prepared by conventional incipient wetness impregnation.Catalytic activities for the methanation of carbon monoxide were investigated.The results show that the best loading of Ni is 15wt%.Their catalytic activities were influenced by the content of TiO2 in the supports.For 15%Ni/60%Al2O3-40%TiO2 catalyst,the conversion of CO is higher than 90%,while the selectivity of CH4 is 100%.Their catalytic activities were enhanced with the increase of reaction temperature in the range of 320℃～440℃.The catalytic activities were decreased with the increase of speed velocity in the range of 5 000 h-1～15 000 h-1.