THF—FER沸石的系列研究—1．晶体结构稳定性

四氢呋喃（THF）-Na2O-SiO2-Al2O3-H2O体系水热合成的THF-FER沸石，经酸交 换-焙烧脱THF（Ⅰ）或焙烧脱THF-酸交换（Ⅱ）的不同方式处理，均可制得低钠H- FER沸石。经XRD，^27Al与^29Si MAS NMR,低温氮吸附等表征证明，通过1273K高温 的热处理和1073K饱和水蒸气下的水热处理，H-FER沸石骨架保持高度稳定。在高温 水蒸气作用下，Si(2Al）容易从骨架上脱离，而Si(1Al）则保持相对稳定，以（Ⅱ ）方法处理，制备的H-FER沸石在水热条件下易产生较多的硅差劲基缺陷。经高温 热和水热处理后，H-FER沸石孔道结构基本保持完美、开放。

Studies on THF-FER Zeolite I . Stability of Crystal Structure

THF-FER (ferrierite) zeolite was synthesized in the reactant system of tetrahydrofuran (THF)-Na-20-Si0-2-AlO-3-H2O. H-FER with very low content of sodium was prepared by two means, ion-exchange-detemplate by calcination ( I ) and detemplate by calcination-ion-exchange ( II ) . The structural stability and the effect of de-aluminum in the framework of H-FER zeolite were investigated by XRD,~ 27A1 and Si MAS NMR as well as the adsorption of nitrogen at 77 K. The framework of H- FER zeolite exhibits very high stability, even calcined at 1273 K for 2 h and treated at 1073 K for 10 h in air flow saturated with water vapor. The H-FER zeolite prepared by means of ( II ) includes the treatment with saturated water vapor at high temperature, Si(2Al) in the framework of H-FER zeolite was easily removed from the framework, whereas the content of Si(lAl) was relatively unchanged. The perfection and the opening of the porous structure for H-FER zeolite still remain after thermal and hydrothermal treatment at high temperatu