| 摘要 |
Fibrous titanium dioxide is prepared by (a) contacting a titanium tetrachloride, or a mixture of titanium tetrahalides, optionally mixed with a transporting gas, at a temp. above 600 degrees C with a molten mass composed of one or more salts of oxyacids, which can form voltatile anhydrides under the reaction conditions, and (b) separating the fibrous titanium dioxide from the reaction mixture. The reaction is pref. carried out with titanium tetrachloride, and a molten mixture of sodium sulphate and magnesium sulphate. The process provides TiO2 whiskers in which the ratio of length to thickness is 300-2000:1, a length of 1000 mu, and a diameter of 1-2 mu. The TiO2 whiskers are useful as a high temp. insulating material, and as filtering material. |
