硅酸盐学报2017，Vol.45Issue(7)：976-983,8.DOI:10.14062/j.issn.0454-5648.2017.07.13
MFI型硅铁沸石水热合成、介孔改性与结构表征
Hydrothermal Synthesis, Mesoporous Modification and Structural Characterization of Ferrisilicate Zeolites with MFI Structure
摘要
Abstract
MFI-type ferrisilicates with various Si/Fe molar ratios were hydrothermally synthesized using inorganic ferric and silica sources. The mesoporous modification of the MFI-type ferrisilicates in proton form was performed via a combined alkali-acid treatment. The crystal structure and porous distribution of precursor and modified zeolites were investigated by X-ray diffraction, Fourier transform infrared spectroscopy, ultraviolet-visible light absorption spectroscopy, N2-adsorption, scanning electron microscopy, and energy dispersive X-ray spectroscopy, respectively. The results show that the intra-grain mesoporostity and removal behavior of T-atoms (T= Si + Fe) are correlated to Si/Fe ratio in framework. The ferrisilicates as-prepared are MFI zeolites with a complete crystallinity, in which most Fe3+ atoms are incorporated into MFI framework. After being subjected to the alkali-acid treatment, the ferrisilicates preserve an adequate crystallinity, a high desilication selectivity and a mesoporosity, and present a two-level mesopore distribution. Moreover, the initial Si/Fe ratio in framework has a crucial effect on the controlled desilication for mesopore formation. The modified zeolites with initial Si/Fe ratios in the range of 60~120 have both greater mesoporostity and removal efficiency of T-atoms.关键词
硅铁沸石/碱酸处理/硅铁比/多级介孔/脱硅选择性Key words
ferrisilicate zeolite/alkali-acid treatment/Si/Fe ratio/hierarchical mesopore/desilication selectivity分类
化学化工引用本文复制引用
韩静宇,王洪涛,张莉,张舒冬,封瑞江,金英杰..MFI型硅铁沸石水热合成、介孔改性与结构表征[J].硅酸盐学报,2017,45(7):976-983,8.基金项目
国家自然科学基金项目(21171083). （21171083）
