磁性纳米固体超强酸的制备研究

Preparation of magnetic nanometer-sized solid superacid

制备了ZrO2/Fe3O4磁性固体酸催化剂,利用XRD、DTA、IR等手段研究了磁性基质对ZrO2的粒子大小、晶化温度、晶型结构及超强酸中心的影响.通过酯化反应考察磁性固体超强酸的催化特性及通过催化寿命实验考察了催化剂的寿命变化情况.结果表明,Co0.5Fe2.5O4磁性基质的引入不但赋予了催化剂以磁性,而且在固体超强酸形成过程中起到延迟ZrO2由四方晶相向单斜晶相的转变,这有助于提高样品的强酸性和催化活性.

Magnetic substrate Fe_3O_4 and ZrO_2 are assembled together,and magnetic solid acid catalyst is prepared. The structure and properties of the synthesized magnetic solid acid are studied by the methods of DTA,XRD,FT-IR.The catalytic activity of magnetic solid acid is studied by esterification ,and the catalysts lives,recovery and variation of magnetic property are also studied.The results showed addition of the magnetic substrate gives catalyst magnetism ,and the impregnation of magnetic substrate delays the transition from ZrO_2(t) to ZrO_2(m) which makes ZrO_2 more stable and magnetic substrate Fe_3O_4 enhances acid center structure of solid acid ZrO_2, on particle size,crystallizing temperature,and crystal structure of ZrO_2.