K含量对纳米K/Fe/β-Mo_2C催化剂CO加氢反应性能的影响  

Influence of K content on performance of nano-structured K/Fe/β-Mo_2C catalysts in CO hydrogenation

作　　者：赵立红 闫捷 房克功[2] 魏灵朝 蒋元力 孙予罕[2,3] 

机构地区：[1]河南能源化工集团研究院有限公司,河南郑州450046 [2]中国科学院山西煤炭化学研究所煤转化国家重点实验室,山西太原030001 [3]中国科学院上海高等研究院,上海201203

出　　处：《天然气化工—C1化学与化工》2014年第3期25-29,共5页Natural Gas Chemical Industry

基　　金：国家自然科学基金重大项目(20590363)

摘　　要：以柠檬酸(CA)为络合剂,采用溶胶-凝胶法制备了K/Fe/β-Mo2C催化剂前驱体,将该前驱体在Ar气氛下程序升温碳化制备了纳米尺寸的K/Fe/β-Mo2C催化剂。考察了K含量对K/Fe/β-Mo2C催化剂织构及CO加氢反应性能的影响。结果表明,K助剂的引入促进了催化剂中β-Mo2C晶粒的长大,适量的K提高了催化剂的比表面积,提高了催化剂的活性和低碳醇选择性,但是过量K助剂的引入在催化剂表面形成了惰性的K2MoO4和K2Mo2O7,覆盖了部分活性中心,降低了催化剂的活性和低碳醇选择性。A series of nano-sized K/Fe/β-Mo2C catalysts were prepared by a modified sol-gel method followed by a temperature-programmed carburization process under argon flow. The effects of K on the texture properties, structure and catalytic performance of the catalysts were investigated. The results showed that the introduction of K increased β-Mo2C particle size of the catalysts, and the addition of proper content of K could improve the surface area, the CO hydrogenation activity and the selectivity to higher alcohols of the catalysts. However, when excessive K was added, the inert K2MoO4 and/or K2Mo2O7 would be formed on the surface of the catalysts, which resulted in that part of the active species were covered and the catalytic activity and selectivity of higher alcohols were decreased.

关 键 词：溶胶-凝胶法 柠檬酸 纳米尺寸 β-Mo2C催化剂 一氧化碳 加氢 混合醇 

分 类 号：O643.36[理学—物理化学] TQ426[理学—化学]