二氧化钛的无机改性

Inorganic Modification of Titanium Dioxide

在一定的温度和压力条件下,采用单质硅溶解法制备用于改性的大粒径硅溶胶,利用表面包覆技术,在TiO2的表面形成致密的SiO2膜,以达到改性的目的。实验得出:在反应温度160℃,反应压力0.5 MPa,反应时间9h,硅粉用量15 g,催化剂用量0.4g的条件下制得分散良好的硅溶胶;通过硅酸钠对pH值的调节来对TiO2浆液进行预分散,并用自制硅溶胶对TiO2浆液进行无机改性,当SiO2/TiO2=3.5%,pH=8时,改性后TiO2浆液分散稳定性有极大改善。

At a certain temperature and pressure conditions, the elemental silicon dissolved method was used for large particle size silica sol modification . Using the surface coated technology, a densed SiO2 film was formed on the surtace of TiO2. The results show that the surface condition of TiO2 coated with SiO2 film changed. The dispersion performance of TiO2 in aqueous solution improved. By FTIR analysis, it can be found that this is not only a physical coating but also a kind of chemically bonding, forming Ti-O-Si bonds on the surface of TiO2. The slurry stability improved greatly after coating with silica sol.