二氧化钛光催化降解蓝色染料的动力学研究

Kinetic study of photocatalytic degradation of blue organic dyes by titanium dioxide

本文选择两种蓝色有机染料——曲利苯蓝与考马斯亮蓝R250为研究对象,使用二氧化钛为催化剂,研究了它们在254nm紫外光下降解的影响因素以及相应的动力学模型。实验结果显示,随着二氧化钛投加量的增加以及反应时间的延长,曲利苯蓝与考马斯亮蓝R250的脱色率均随之升高;而增大曲利苯蓝与考马斯亮蓝R250的起始浓度,它们的脱色率则随之下降。此外,溶液p H也对对于这两种染料的降解存在一些影响。在二氧化钛的催化下,曲利苯蓝与考马斯亮蓝R250的降解均符合准一级Langmuir-Hinshelwood方程。

This paper selected two blue organic dyes, trypan blue and coomassie brilliant blue R-250, as substrates under the irradiation of 254nm UV light with the existence of titanium dioxide powder for photocatalytic degradation study. Both the parameters affecting the photocatalysis and the characteristic kinetic model were also investigated. The experimental results show that the decoloring ratio of trypan and coomassie brilliant blue R-250 solutions increase along with the addition of titanium dioxide amount and reaction time but decrease with the addi- tion of starting concentration of these two dyes. Additionally, the solution pH has some effects to the photocatalytic degradation of these two dyes. The photodegradation of these two dyes was also found to obey pseudo-first order kinetics according to the Langmuir-Hinshelwood model.