摘要
利用有机硅化合物与分子筛表面羟基有较强的反应性，以硅烷气体作为改性剂，对ＨＺＳＭ－５表面羟基进行了改性研究。并用ＸＲＤ、ＥＳＣＡ、ＩＲ、ＭＡＳＮＭＲ、化学分析等手段表征了改性样品。发现增硅的同时，也发生了脱铝并且迂移至沸石外表面的现象。最后，对增硅脱铝可能的机理作了讨论。
It has been proved that the modification of HZSM-5 zeolites is very effectivewhen silanes react with surface hydroxy groups of the zeolites. The framework structure ofzeolite samples was not destroyed as shown by the XRD and IR patterns , but silanization anddealumination took place at the same time in the course of silanization, Chemical arialysis,ESCA analysis, and ￣(29)Si and ￣(27)Al MASNMR investigations further displayed that a part of thealumium broke away from the framework of the zeolites and migrated to the outer surfaceforming a separate phase of Al_2O_3 and Al(OH)_3. The mechanism of silanization and dealumi-nation was discussed.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
1994年第4期393-399,共7页
Journal of Fuel Chemistry and Technology
