摘要
在不含有机模板剂体系(OSDAs)中,利用异相晶种(T型分子筛)诱导快速合成出纯相的低硅菱沸石分子筛。采用XRD、SEM、TEM、27Al MAS NMR和紫外拉曼等手段表征分子筛的结构属性和形貌特点。详细研究了菱沸石分子筛的晶化过程以及晶种添加量、nAl2O3/nSi O2、nH2O/nSiO2和碱度对菱沸石分子筛晶化的影响,并探讨T型分子筛晶种诱导合成菱沸石分子筛的晶化机理。原位合成体系中仅形成L型分子筛晶相,而一定量T型分子筛异相晶种的加入诱导溶胶快速制备出纯相的菱沸石分子筛。T型分子筛晶体在一定的水热条件下不断溶解而释放的六元环(6R)和四元环(4R)迅速形成菱沸石分子筛特征笼(CHA笼),抑制了L型分子筛特征单元和特征笼(不含四元环的CAN笼)的形成。
Pure-phase low-silica chabazite zeolites were rapidly synthesized by the addition of heterogenous seeds （zeolite T） without organic structural directing agents （OSDAs）. Structural properties and morphology characteristics of the products were characterized using XRD, SEM, TEM, 27Al MAS NMR and UV Raman spectroscopy. Crystallization process of chabazite and the various parameters such as seed content, nAl2O3/nSiO2, nH2O/nSiO2 and alkalinity on the crystallization of crystals were investigated in detail. The formation mechanism of chabazite zeolite induced by zeolite T seed was also discussed. Only zeolite L was formed in the in-situ synthesis system while pure chabazite zeolite was fast obtained by adding a certain amount of zeolite T into the gel. The six-membered （6R） and four-membered rings （4R） released from the dissolved zeolite T under certain hydrothermal conditions rapidly formed the characteristic unit of chabazite zeolite （CHA cage）, which inhibited the formation of the characteristic unit and characteristic cage of zeolite L （the CAN cage without four-membered ring）.
作者
李玉琴
胡娜
张飞
朱美华
吴婷
陈祥树
LI Yu-Qin;HU Na;ZHANG Fei;ZHU Mei-Hua;WU Ting;CHEN Xiang-Shu(Institute of Advanced Materials（IAM）,State-Provinee Joint Engineering Laboratory of Zeolite Membrane Materials College of Chemistry and Chemical Engineering,Jiangxi Normal University,Nanchang 330022,China)
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2018年第12期2143-2152,共10页
Chinese Journal of Inorganic Chemistry
基金
国家自然科学基金(No.21476099和No.21766010)
国家国际科技合作专项(No.2015DFA50190)
江西省科技计划(No.20171BCB24005)资助项目
关键词
菱沸石分子筛
水热合成
异相晶种
有机模板剂
chabazite zeolite
hydrothermal
synthesis
heterogenous seeds
OSDA-free
