Development and Design of New Heat-resistant Zeolite

沸石在裂化、烃类异构化、烷基化、甲醇制汽油等方面具有重要的工业用途。然而，许多具有高活性、高选择性的沸石催化剂由于缺乏耐热性和耐水性而未能实现商业化。由于沸石催化剂的失活过程不容易从实验上弄清楚，除了精心的实验工作外，还需要理论方法。本文采用实验技术和理论方法对沸石催化剂的失活过程进行了研究。重点研究：(1)利用高分辨率透射电子显微镜（HRTEM）研究沸石脱铝机理；(2)研究晶体生长机理；(3)利用分子动力学（MD）和计算机图形学再现沸石热破坏过程；(4)利用密度泛函（DF）方法研究沸石水失活过程。结果表明：(1)可以获得沸石脱铝机理的详细信息；(2)可以设计新型沸石的可能性；(3)可以用MD法预测新型沸石的耐热性；(4)可以用DF法预测反应的耐水顺序。因此，我们的研究取得了进展，取得了成功，取得了重要的成果。此外，我们将尝试在更多样化的模型系统中提取更多有用的信息。

Zeolite are industrially important catalysts because of their applications to cracking, hydrocarbon isomerization, alkylation, and meethanol-to-gasoline processing etc. However, many zeolites catalysts with high activity and high selectivity have not been commercialized because of their lack of heat-resistance and water-resistance. Since it is not easy to clarify the deactivation process of zeolite catalysts experimentally, theoretical methods are desirable in addition to elaborate experimental work. In this investigation we studied the deactivation process of zeolite catalysts by using experimental technique and theoretical method. Particularly we investigated in detail : (1) the dealumination mechanism of zeolite by high-resolution transmission electron microscopy (HRTEM), (2) the mechanism of crystal growth, (3) reproducing the thermal destruction of zeolites molecular dynamics (MD) and computer graphics, (4) the deactivation process by water by density functional (DF) methods. As results, it was clarified that : (1) detailed information of the dealumination mechanism of zeolite can be obtained, (2) the possibilities of the design of new novel zeolites, (3) the heat-resistance of new novel zeolites by MD method can be predicted, and (4) the order of water-resistance in a reaction by DF method can be predicted. So it is considered that out investigation progressed and was successful to obtain important and fruitful results. Furthermore we will try to extract more useful information assuming more diversified model system.