铈、铌改性镁铝尖晶石作为催化降烯烃助剂的研究  

Ce/MgAl_2O_4 and Nb/MgAl_2O_4 Additives for Olefin-Reducing in Fluid Catalytic Cracking Gasoline

作　　者：任彦瑾[1] 施力[1] 

机构地区：[1]华东理工大学化工学院,上海200237

出　　处：《中国稀土学报》2008年第1期1-5,共5页Journal of the Chinese Society of Rare Earths

摘　　要：采用溶胶凝胶法制备Ce/MgAl2O4,Nb/MgAl2O4流化催化裂化(FCC)汽油降烯烃助剂,在小型固定床反应装置上考察了不同镁铝配比和Ce,Nb改性对助剂降烯烃性能的影响。并采用XRD和IR分析手段对助剂的降烯烃机制进行了分析。结果表明,经Ce改性后助剂的降烯烃活性较Nb改性高,镁铝比为1∶1时,添加20%Ce元素的助剂可将烯烃的体积分数降低30%以上。XRD结果表明Ce,Nb的加入增强了镁铝尖晶石的氢转移活性,IR分析表明弱酸中心有利于助剂降烯烃。Additives for fluid catalytic cracking（FCC） process, based on MgAl2O4 having various Mg/Al mole ratios, were prepared by sol-gel method. Test were carried out in a fix bed reactor to observe the effect of olefin reduction in FCC gasoline, and the influence of Mg/Al mole ratio, the modification of Ce and Nb on the additive performance were studied as well. The results indicated that the additives with a Mg/Al mole ratio of 1.0 showed the best reaction activity. The activ-ities of additives modified by Ce and Nb were also proposed. When the content of Ce was 20%, the olefinreducing rate was over 30% in FCC gasoline. The reaction mechanism was also studied, XRD results showed that Ce/MgAl2O4 could improve hydrogen and Nb/MgAl2O4 additives migration reaction activity, acidity of the additives was researched in Pyridine-IR, it showed that weak acid amounts affected activity of the additives.

关 键 词：催化裂化 溶胶凝胶 助剂 降烯烃 氢转移 稀土 

分 类 号：TE624.94[石油与天然气工程—油气加工工程]