SO_4~(2-)/TiO_2、PO_4~(3-)/TiO_2、BO_3~(3-)/TiO_2系列固体酸的酸性、结构和晶相的研究

制备了ＳＯ４２－／ＴｉＯ２（Ⅰ）、ＰＯ４３－／ＴｉＯ２（Ⅱ）、ＢＯ３３－／ＴｉＯ２（Ⅲ）系列固体酸。用ＩＲ、Ｒａｍａｎ光谱对该系列固体酸进行结构表征，结果表明ＳＯ４２－与ＴｉＯ２表面的结合为螯合式双配位结构和共价硫酸盐共存，ＰＯ４３－与ＴｉＯ２表面的结合为桥式三配位结构，ＢＯ３３－与ＴｉＯ２表面的结合为单齿单配位结构和螯桥混合式三配位结构共存。用由溶液中正丁胺的吸附等温线测定固体表面酸度的方法测定了样品的酸量，结果表明酸量大小为Ⅰ＞Ⅱ＞Ⅲ。用ＸＲＤ技术对该系列固体酸进行考察，衍射图分析提示该系列固体酸主要都为锐钛矿型晶型，但Ⅰ、Ⅱ、Ⅲ中又各自夹杂其它不同的晶型

Studies on the Acidity, Structures and Crystalline Phases of SO42-/TiO2,PO43-/TiO2,BO33-/TiO2 Solid Acids

A series of SO42-/TiO2(),PO43-/TiO2() ,BO33-/TiO2() solid acids are prepared. The structures of this series of solid acids are characterized by IR and Raman spectra. It is indicated that SO42- is combined with metal ions of TiO2 in a chelating bidentate mode as well as covalency sulphates, PO43- is combined with metal ions of TiO2 in a three triply bridging mode, and BO33- is combined with metal ions of TiO2 in a monocoordination mode as well as a chelating and bridging tridentate mode.The acid content of the solid acid is determined by measuring the surface acidity of solids based on the adsorption isotherms of nbutylamine in solution. The result indicates that the sequencef the acid content is > >.Using XRD technology the nature of this series of solid acids is studied. The result indicates that this series of solid acids are mainly an anatase, but they are also mixed up with other different crystalline phases.