摘要
采用干胶转化法,在晶种辅助下,制备出多级孔ZSM-5沸石,考察了晶种加入量、水加入量和晶化时间等因素对多级孔沸石结构和形貌的影响。结果表明:加入晶种,大大加快了沸石合成的晶化速率,无定形硅铝凝胶直接在晶种表面形成的水膜中溶解并就近快速生长为ZSM-5纳米沸石,纳米沸石相互聚集,并在纳米沸石间形成了介孔孔道。通过调节晶种加入量、水加入量和晶化时间,可以调节纳米沸石的大小,进而改变介孔孔道的大小。纳米沸石相互聚集形成了同时含有微孔和介孔的多级孔ZSM-5沸石,在催化氧化苯乙烯重排制备苯乙醛反应中的稳定性较传统沸石提高了5倍。
Hierarchical ZSM-5 zeolite was synthesized by a seed-assisted dry-gel conversion method, and the effects of seed amount,deionized water amount and crystallizing time on the structure and morphology of hierarchical zeolite were investigated. The results show that the crystallization rate of zeolite is increased with seed addition. Amorphous silica–aluminium gel can directly dissolve in the water film condensing on the seed surface and rapidly grew into ZSM-5 nano-zeolite near the seed. Simultaneously, nano-zeolites aggregate and some mesoporous channels are formed between the nano-crystals. The size of nano-zeolite and the resulting mesoporous pores can be adjusted by seed amount, deionized water amount and crystallizing time. The catalytic stability of the resulting hierarchical ZSM-5 zeolite is improved by nearly 5 times, compared with the conventional zeolite in the isomerization of styrene oxide to phenylacetaldehyde.
作者
勾明雷
韩志远
刘一君
李晨铭
宋文生
刘振
GOU Minglei;HAN Zhiyuan;LIU Yijun;LI Chenming;SONG Wensheng;LIU Zhen(School of Chemical Engineering and Pharmaceutics,Henan University of Science and Technology,Luoyang 471023,Henan,China)
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2022年第3期805-811,共7页
Journal of The Chinese Ceramic Society
基金
河南科技大学青年骨干教师培养计划(4008-13450008)
河南省重点攻关项目(182102310795)。
关键词
干胶转化
晶种
多级孔
纳米沸石
催化性能
dry-gel conversion
seed crystal
hierarchical pore
nano-zeolite
catalytic performance
