Design and Applications of Microporous Crystals with Molecular Recognition Properties

本课题的目的是合成具有高形状选择性和特殊化学亲和性的新型微孔晶体，用于吸附、催化转化和分离。1.化学改性柱撑粘土的分子识别用Na离子负载改性氧化铝柱撑粘土，使其对二甲苯异构体的分离表现出高选择性。2.复合氧化物柱撑粘土的合成及其吸附性能研究合成了Al_2O_3-NiO复合氧化物柱撑粘土。所得柱撑结构比氧化铝柱撑粘土具有更高的热稳定性。3.具有高比表面积和高热稳定性的硅柱撑粘土的合成硅溶胶粒子带负电荷，不能引入粘土的硅酸盐层之间。二氧化硅溶胶粒子通过在表面上沉积氧化铁而带正电。用改性的溶胶颗粒柱撑蒙脱石。4.非硅酸根柱撑材料的合成及其吸附和催化性能研究用SiO2柱撑层状结构的钛酸锰（RbxMnxTi 2-xO 4），并对其进行了表征。吸附研究表明，柱撑化合物具有类似沸石的微孔结构。5.高取向柱撑粘土膜的制备及气体渗透性将柱撑粘土薄膜沉积在多孔氧化铝基底上。膜没有针孔和裂纹。各种气体的渗透率被测量到高达500 ℃。氢和氦显示出通过层间孔的活化扩散。

The purpose of this project is to synthesize new microporous crystals with high shape-selectivity and specific chemical affinity for adsorption, catalytic conversion and separation.1.Molecular recognition by chemically modified pillared claysAlumina pillared clay was modified by Na ion loading, which showed high selectivity to the separation of xylene isomers. Chemical modification of SiO2-TiO2 sol pillared clays was also studied.2.Synthesis of pillared clays with mixed oxides and their adsorption propertiesPillared clays with Al2O3-NiO mixed oxide were synthesized. The resulting pillared structure showed higher thermal stability than alumina pillared clays.3.Synthesis of silica pillared clays with high surface area and high thermal stabilitySilica sol particles are negatively charged and cannot be introduced between the silicate layrs of clay. The silica sol particles were positively charged by the deposition of iron oxide on the surface. Montmorillonite was pillared with the modified sol particles. On washing with acid, the iron oxide was easily removed, and silica pillared clays were obtained, which had high surface area and high thermal stability4.Synthesis of non-silicate pillared materials and their adsorption and catalytic propertiesA layr structured manganese titanate, RbxMnxTi2-xO4, was pillared with silica. The adsorption studies suggested that the pillared compounds had micropores like zeolites. The compounds showed a high catalytic activity against the oxidation of CO.5.Preparation and Gas permeability of highly oriented pillared clay membranePillared clays were deposited as thin membrane onto porous alumina substrate. The membranes were free from pin holes and cracks. Permeabilities of various kinds of gasses were measured up to 500ﾟC.Hydrogen and helium showed an activated diffusion through the interlayr pores.