低温制备纳米TiO_2溶胶整理棉织物对染料的降解

Cotton fabric finished with low temperature prepared nano-TiO_2 sol and its catalysis for dye degradation

在室温条件下使钛酸丁酯水解制备纳米TiO2溶胶,然后利用后整理技术将其负载于棉纤维表面得到纳米TiO2整理棉织物。在对纳米TiO2溶胶及其整理棉织物表征的基础上,将纳米TiO2整理棉织物作为光催化剂应用于有机染料罗丹明B的降解反应中,重点考察了水与钛酸丁酯的物质的量比、陈化时间以及纳米TiO2整理棉织物增重率对脱色率的影响,并研究了纳米TiO2整理棉织物的重复利用性和罗丹明B的降解反应动力学。结果表明,在纳米TiO2溶胶的制备中,水与钛酸丁酯物质的量比的增加能形成粒径小而均匀的溶胶。通过浸烘整理工艺能使纳米TiO2溶胶在棉纤维表面形成锐钛型纳米TiO2结晶薄膜。当纳米TiO2整理棉织物作为光催化剂时,罗丹明B的脱色率随增重率的增加而提高,并且水与钛酸丁酯物质的量比的增加和陈化时间的延长都能够明显改善其光催化活性。纳米TiO2整理棉织物作为光催化剂可以重复使用,并且罗丹明B在纳米TiO2整理棉织物存在下的光催化降解反应符合假一级动力学反应模型。

The nano-TiO2 sol was prepared at room temperature through hydrolysis of tetra-n-butyl titanate,and then loaded on the surface of cotton fabric using finishing method,thus obtained nano-TiO2 finished fabrics,that were characterized and used as photocatalysts for oxidative degradation of Rhodamine B in water.Some factors affecting degradation such as molar ratio of water to n-butyl titanate,aging time and weighting percentage of the nano-TiO2 finished fabrics were investigated with respect to the decoloration value,and reuse of nano-TiO2 finished fabrics and degradation reaction kinetics of Rhodamine B were also examined.The results showed that increasing molar ratio of water to n-butyl titanate led to the smaller particle size and more homogeneous nano-TiO2 sol during its preparation,and the nano-TiO2 sol could form an anatase TiO2 nano-crystalline film on the surface of cotton fabrics through padding-curing process.Increasing the weighting percentage of the nano-TiO2 finished fabrics significantly accelerated dye degradation,and increasing molar ratio of water to n-butyl titanate and aging time could also improve the photocatalytic activity of the nano-TiO2 finished fabrics.In addition,the nano-TiO2 finished fabrics could be reused for dye degradation,and the degradation of Rhodamine B in the presence of nano-TiO2 finished fabrics followed the pseudo-first order kinetics.