摘要
通过ＣＯ脉冲化学吸附以及对吸附态ＣＯ和ｃｏ＋Ｈ＿２反应进行程序升温表面反应（ＴＰＳＲ），发现１％Ｒｕ／ｓｉＯ＿２和１％Ｒｕ／ＡＬ＿２Ｏ＿３催化剂的ＣＯ吸附量随焙烧温度的升高而降低。且根据５１３Ｋ和室温吸附ｃｏ的ＴＰＳＲ不同，认为存在两类不同活性中心。Ⅰ类中心：金属钌与载体的相互作用弱，易吸附ＣＯ；Ⅱ类中心：金属与载体的相互作用强，较难吸附ＣＯ。随焙烧温度升高，金属与载体作用增强，Ⅱ类中心增多。在微型流动反应器上ＣＯ中压加氢发现经６７３Ｋ焙烧的样品的活性及长链烃的生成量和烯／烷比均大于１２０℃烘干的样品，因此认为，Ⅰ类中心为加氢中心，Ⅱ类中心为链增长中心。
% Ru/SiO_2 and 1% Ru/Al_2O_3 catalysts have been studied by CO pulse chemical adsorption,temperature programmed surface reaction(TPSR ) of adsorbed CO and cO + H_2 reaction. The amount of adsorbed CO on both catalysts decreased with the increasing of calcination temperature of catalysts. Two diffefent kinds of active sites were proposed according to different TPSR results of CO adsorbed at room temperature and 513K respectively。On the first kind of sites,the interaction between the ruthenium metal and the support was weak, and CO was easier to be adsorbed. On the second kind of sites ,the interaction between metal and support was stronger and CO was more difficult to be adsorberl. Higher calcination temperature of the catalysts led to stronger interaction between metal and support and more sites Ⅰwas formed. The CO hydrogenation in a flow microreactor under medium pressure showed that the catalysts calcined at 673K withhigher activity,larger amount of long chain hydrocarbons and higher ratio of olefin to paraffin than those calcined at 393K. Therefore ,it is suggested that sitesⅠwas responsible for hydrogenation and sites Ⅱ for chain growth.
出处
《煤化工》
CAS
1994年第1期28-33,共6页
Coal Chemical Industry
关键词
催化剂
二氧化碳
吸附
氢化
钌
ruthenium CO hydrogenation synthesis gas synthesis of hydrocarbons synthetic fuel
