新型两亲性含钛β沸石的制备与表征

Preparation and Characterization of a Novel Amphiphilic Ti-β Zeolite

将Ti β沸石经过正十八烷基三氯硅烷改性制得两亲性含钛β沸石 ,并通过XRD ,FT IR ,UV vis和N2 吸附 -脱附等手段对其进行了表征 .同改性前样品相比 ,制备出的两亲性含钛β沸石保持了原来的晶体结构 ,其BET比表面积和BJH孔容均稍有下降 .FT IR和UV vis结果说明该沸石骨架中存在四配位钛 ,从而有可能成为催化烯烃环氧化反应的活性中心 .由于外表面部分覆盖有憎水性的硅烷基团而其它部分呈现亲水性 ,该两亲性含钛沸石分布于水 /油两相界面处 。

An amphiphilic Ti-β zeolite was pr epared from Ti-β modified with n-octadecyltrichlorosilane and characteriz ed by XRD, FT-IR, UV-vis and nitrogen adsorption-desorption techniques. Compa red to the parent zeolite, the resulting amphiphilic Ti-β zeolite remained t he original crystal structure with a smaller specific surface area and BJH volum e of pores. FT-IR and UV-vis spectra indicated the existence of tetrahedrally coordinated Ti atoms, which may act as active sites for epoxidation of olefin. D ue to the partial coverage of the external surface with the hydrophobic alkylsil ane groups and the hydrophilicity of the rest of the surface, this amphiphilic z eolite was oriented at the water-organic boundary. Such a zeolite may be utiliz ed as phase-boundary catalyst in systems without use of co-solvents.