Abstract: Formed TiO_２ supports were prepared by extrusion process using TiO_２ powder as raw material．The influence of the kinds of peptizers，the contents of citric acid，the contents of nitric acid，and the binder/citric acid mass ratios on properties of the formed TiO_２ supports were investigated，and these supports were characterized by crushing strength test，BET and SEM methods．The results show that all the peptizers can improve the crushing strength of the formed TiO_２ supports；however， peptizers have little effect on the surface area of the supports． The added citric acid can remarkably increase the crushing strength of the formed TiO_２ supports，and the maximum value can be obtained when mass fraction of 3% citric acid is added． Addition of HNO_３ can increase the crushing strength and narrow the pore size distribution of the formed TiO₂ supports．It is also found that the formed TiO_２ supports with high crushing strength，narrow pore size distribution and little surface defects can be prepared using the suitable binder/citric acid mass ratio．Under the preparation conditions of nitric acid mass fraction of 3%，binder/citric acid mass ratio of 4:6 and calcination temperature of 700 ℃，the crushing strength，surface area and pore volume of the formed TiO_２ support can reach 125.8 N／cm，48.6 m^２ ／g and 0.33 cm^３ ／g，respectively．

Key words: Titanium dioxide , Extrusion molding , Support , Peptizer , Citric acid , Nitric acid

摘要： 以 TiO 2 粉体为原料 ,采用挤条成型的方法制备了TiO₂成型载体。考察了制备过程中胶溶剂类型柠檬酸含量﹑硝酸含量以及粘结剂/柠檬酸复配比等对TiO₂成型载体性能的影响，并用抗压强度测试﹑比表面积(BET)﹑扫描电镜(SEM)等手段进行了表征。结果表明，胶溶剂的加入均可不同程度提高TiO₂成型载体的抗压强度，但对载体的比表面积影响不显著。柠檬酸质量分数3%时载体的抗压强度最高；加入硝酸可提高载体的抗压强度外，还可使载体的孔径分布集中。采用适宜的粘结剂 /柠檬酸复配比，有利于制备抗压强度高﹑孔径分布集中﹑表面缺陷少的TiO₂成型载体。在硝酸质量分数3%、m(粘结剂)/ m(柠檬酸)为4∶6，焙烧温度700℃的制备条件下，载体的抗压强度﹑比表面积和孔容可分别达125 .8 N/cm，48 .6 m² / g和 0 .33 cm³ / g。

关键词: 二氧化钛 , 挤出成型 , 载体 , 胶溶剂 , 柠檬酸 , 硝酸