机械力化学法制备TiO_2/高岭土复合光催化剂

Preparation of TiO_2/Kaolinite Composite Photocatalyst by Mechnochemcial Method

以高岭土为载体,采用机械力化学法制备了TiO2/高岭土复合光催化剂。以甲基橙溶液的光催化降解率作为评价指标,采用正交实验法,研究了纳米TiO2和高岭土混合研磨体系中固体浓度、球料比、复合研磨时间以及纳米TiO2的含量对复合材料光催化降解率的影响。实验结果表明,采用机械球磨技术可以制备具有光催化性能的TiO2/高岭土复合光催化剂。当高岭土湿磨时间为60min,纳米TiO2和高岭石混合研磨体系中固体浓度20%、球料比5∶1、复合研磨时间30min、纳米TiO2的含量为33.3%时,该复合材料对甲基橙的光催化降解率为69%,高于纯TiO2的光催化降解率。

TiO2/kaolinite composites photocatalyst were prepared by mechano-chemical method in a stirred mill.Methyl orange was chosen as the model compound to examine the photocatalytic efficiency of the composites.Through orthogonal single factor experiment,the effects of milling conditions,such as the solid particle concentration in suspensions,weight ratio of ball-to-powder,milling time of kaolinite together with titania,and dosage of titania on photocatalytic degradation performance were examined.The results showed that TiO2/kaolinite composite photocatalyst could be prepared by using ball milling technique.The optimal technique conditions of TiO2/kaolinite composites were as follows：grinding time of kaolinite was 60 min,solid contentration of kaolinite mixed with TiO2 system was 20%,ball to powders ratio was 5：1,mixed grinding time was 30 min,dosage of TiO2 was 33.3%.Under these optimal conditions,the photocatalytic degradation efficiency reached over 69%,which was beyond that of pure TiO2.