Microporous and Mesoporous Materials ( IF 4.8 ) Pub Date : 2019-10-23 , DOI: 10.1016/j.micromeso.2019.109821 Dongxue Guo , Chengxiang Shi , Hui Zhao , Rui Chen , Shaohua Chen , Pingchuan Sun , Tiehong Chen
Many great efforts have been devoted to the synthesis of hierarchically zeolites due to their potentially significant technological applications for catalytic reactions involving bulky reactant/products. In this work, we report a facile hydrothermal route to prepare mesoporous silicalite-1 with plentiful intracrystalline mesopores (5–20 nm) using poly (acrylic acid) (PAA) as a mesoscale template. During the crystallization process, the PAA chains served as the space occupant for intracrystalline mesopores, meanwhile, a small amount of amphiphilic organosilane (dimethyloctadecyl-[3-(trimethoxysilyl)-propyl]-ammonium chloride, TPOAc) acted as auxiliary template to enhance the connection between the growing crystal domains and the PAA chains. After calcination, the mesopore template PAA chains were burned out, and zeolite with intracrystalline mesopores could be obtained, giving rise to a combination of type I & IV N2 adsorption/desorption isotherms. The alkali metal salts in the synthesis system facilitated the formation of mesoporous structured zeolites. In order to enhance the acidic sites, mesoporous zeolite Al-ZSM-5 with intracrystalline mesopores was also synthesized by introducing aluminum source in the synthesis.
中文翻译:
以聚丙烯酸酯为中尺度模板,用于合成具有大量晶内介孔的MFI沸石
由于分级沸石的合成在涉及庞大的反应物/产物的催化反应中的潜在重大技术应用,因此已经进行了许多巨大的努力。在这项工作中,我们报告了一种简便的水热路线,以聚丙烯酸(PAA)为中尺度模板,可以制备具有大量晶内介孔(5-20 nm)的中孔硅沸石-1。在结晶过程中,PAA链占据了晶内介孔的空间,同时,少量的两亲有机硅烷(二甲基十八烷基-[3-(三甲氧基甲硅烷基)-丙基]-氯化铵,TPOAc)作为辅助模板来增强增长的晶域和PAA链之间的连接。煅烧后,中孔模板PAA链被烧尽,2个吸附/解吸等温线。合成系统中的碱金属盐促进了介孔结构沸石的形成。为了增强酸性部位,还通过在合成中引入铝源来合成具有晶内中孔的介孔沸石Al-ZSM-5。