镁铝尖晶石的制备及其催化降烯烃性能研究

Study on preparation of magnesia-alumina spinel additive and its performances of catalytic olefin reduction

采用溶胶-凝胶法制备出一种可以降低催化裂化(FCC)汽油烯烃含量的镁铝尖晶石催化助剂,在小型固定床反应装置上考察了其催化降烯烃效果,并对镁铝尖晶石的制备条件和不同镁铝的物质的量比对降烯烃效果的影响进行了研究,对助剂的催化降烯烃机理进行了分析。实验结果表明,制备温度为80℃,镁铝的物质的量比为1∶1时,助剂可将烯烃的体积分数降低20%以上。助剂的降烯烃活性主要是晶胞常数最大的MgAl2O4.MgO尖晶石促进了氢转移反应。

Magnesia - alumina spinel additives for FCC process, were prepared by sol - gel method. Test were carfled out in a fix bed reactor to observe the effect of olefin reduction in FCC gasoline, and the influence of preparation temperature and Mg/Al amount - of - substance ratio were studied as well. Resuhs indicated that the additives prepared at 80 ℃ and having a Mg/Al amount - of - substance ratio of 1.0 showed the best reaction activity,the olefin - reducing rate was over 20% in FCC gasoline. The reaction mechanism was also studied. XRD resuhs showed that MgAl2O4· MgO spinel could improve hydrogen migration reaction activity.