PTFE/TiO_2复合膜光催化降解水中罗丹明B研究

Photocatalytic Degradation of Rhodamine B in Aquatic Solution by PTFE/TiO_2 Composite Film

以P25 TiO_2为催化剂、聚四氟乙烯乳液(PTFE)为粘结剂,采用辊压法制备了PTFE/TiO_2复合膜催化剂,并对其进行了SEM和XRD表征。结果表明:TiO_2与PTFE乳液的质量比为4:1时其表面最为平整且分布着均匀的空隙。此外,PTFE的引入并没有改变TiO_2的晶相结构与衍射峰强度。另外,随着光照时间的延长,PTFE/TiO_2复合膜催化表面·OH自由基产生量呈线性增加,且Rh B分子在553 nm处特征吸收峰强度逐渐降低。经过150 min光照后,Rh B的光催化降解率达到87%。连续重复使用14次之后,PTFE/TiO_2复合催化膜的光催化效率仅下降2%左右,这表明其可能在废水深度处理领域得到实用化应用。

In this study, PTFE/TiO2 composite film was fabricated through rolling process by use of P25 TiO2 as catalyst and PTFE latex as binder. The resulting samples were then characterized by SEM and XRD techniques. The results showed that the optimized quality ratio of Ti〇 2 to PTFE latex was 4：1, in which the PTFE/Ti〇 2 composite film possessed most smooth surface and uniform pore structure. Addition of PTFE latex didn’ t change the crystalline phase structure and diffraction peak intensity of Ti〇 2 . Moreover, with the extension of light irradiation, the yield amount of＊OH at PTFE/Ti〇 composite film/water interface increased linearly and the characteristic adsorption peak intensity of RhB at 553 nm decreased gradually. Within 150 min of illumination, photocatalytic efficiency of RhB reached to 87%. After 14 times of continuous reuse, the photocatalytic efficiency only declined by 2%, indicating that such PTFE/Ti〇 composite film could be practically applied in the field of advanced wastewater treatment.