助剂CeO2对Co/Al2O3催化剂上F-T合成反应性能的影响

 在用于F－T合成的Co／Al2O3催化剂中加入少量助剂，能够提高CO转化率和C5＋烃选择性．主要考察了助剂CeO2添加量和催化剂焙烧温度等因素对F－T合成反应的影响，并通过程序升温还原、程序升温氧化及X射线衍射等手段对催化剂进行了表征．结果表明，在Co／Al2O3催化剂中加入少量CeO2（n（Ce）／n（Co）＝0．1～0．14），能够有效提高催化剂的催化活性和C5＋烃选择性；焙烧温度则以相反的趋势控制F－T反应活性和链增长几率；助剂的加入降低了催化剂的起始还原温度，改善了催化剂的还原性能．但是，催化剂的积碳量有所增加，经10h反应后，催化剂上存在两种类型的积碳．

Promotion Effect of Ceria on Fischer-Tropsch Synthesis Performance over Co/Al2O3 Catalyst

The effects of ceria-loading and calcination temperature oncatalytic performan ce of Co/Al2O3 in Fischer-Tropsch synthesis were studied, and the catalyst samples were characterized by means of temperature-programmed reduction (TPR), temperature-programmed oxidation (TPO) and XRD techniques. The results showed t hat the addition of small amount of ceria to Co/Al2O3 catalyst (n (Ce)/n(Co)=0.1～0.14) can increase the CO conversion and C5+ hydrocarbons selectivity, while the calcination temperature can co ntrol both the chain growth probability and CO conversion with reverse trend. Th e TPR and TPO experiments showed that the addition of small amount of ceria can improve the reducibility of the catalyst, but the amount of cabon-deposition i ncreases, and there are two carbon-deposition species on the catalyst after rea ction for 10 h.