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以NaY沸石为原料,用SiCl_4同晶取代法制备了不同硅铝比且具有高结晶度的八面沸石,进一步将样品交换成铵型。还制备了超稳Y样品及铝交换型八面沸石。研究结果表明,随骨架硅铝比提高,八面沸石的骨架稳定性、热稳定性及水热稳定性均得到很大改善。骨架外铝会使较低硅铝比样品的水热稳定性变差。钠型及铵型样品在不同硅铝比时,对稳定性有不同影响。在骨架硅铝比相近情况下,SiC1_4脱铝沸石(DNH_4Y)较水热法脱铝沸石(USY)有好得多的热稳定性,然而二者却具有相近的水热稳定性。
NaY zeolite as raw material, SiCl_4 isomorphous substitution method was prepared with different silica to aluminum ratio and high crystallinity Faujasite zeolite, the sample was further exchanged for ammonium type. Ultrastable Y samples and aluminum-exchanged faujasite were also prepared. The results show that the skeleton stability, thermal stability and hydrothermal stability of faujasite zeolite have been greatly improved with the increase of Si / Al ratio. The extra-framework aluminum will deteriorate the hydrothermal stability of the lower Si / Al ratio samples. Sodium and ammonium samples at different Si-Al ratio, have different effects on the stability. SiC1_4 dealuminated zeolite (DNH_4Y) has much better thermal stability than hydrothermally dealuminated zeolite (USY) when the framework Si / Al ratio is similar, however, both have similar hydrothermal stability.