纳米级多孔钛膜的研制

Study on nanomemter aperture of porous Ti membranes

以钛粉为原料,加入适量的硬脂酸锌、无水乙醇和二甲基甲酰胺制钛粉浆,通过浸涂法制备出具有纳米级孔径的多孔钛膜.探讨了硬脂酸锌含量对膜孔隙特征及渗透分离特性的影响.实验结果显示,烧结出的多孔膜中仅含钛元素,而且膜的结构完整,具有孔道连通的三维结构.膜的厚度、孔径大小及分布随Ti粉浆中硬脂酸锌含量的增加而减小,但膜的分离能力却随硬脂酸锌的增加而增强.当硬脂酸锌的质量分数大于80%时,膜的最可几孔径小于50 nm,而且硬脂酸锌的大幅度增加不会导致纯水通量的大幅度减少,但对分子量大于156 000的物质的截留率却大幅度提高,故该膜可作为超滤膜使用.

A porous Ti membrane with nanomemter apertures for ultrafilteration was prepared by dip - coating. The Ti powder, zinc stearate, ethanol absolute and dimethylformamide were mixed together for Ti slurry. The effects of zinc stearate on the properties of the porous membrane were investigated. The membrane only con- taines Ti element by X- ray diffraction, and has a good integrity structure and pores interconnected by scanning electron microscope images. The thickness of membrane, the size and distribution of the pores decrease along with the increase of zinc stearate content in Ti slurry,however, the retention rate of proteins gradually increas- es. When the content of zinc stearate in green body exceeds 80 %, the most probable pore size is less than 50 nm and the flux of pure water doesn＇t obviously decrease along with the rapidly increase of zinc stearate, however, the passage of large molecular substances with molecular weight over 156 kDa is restricted.