Xia Qi-Bin, Huang Si-Si, Zhang Zhi-Juan, Li Zhong
Key Laboratory of Enhanced Heat Transfer and Energy Conservation of the Ministry of Education, South China University of Technology, Guangzhou 510640, China.
Huan Jing Ke Xue. 2009 Nov;30(11):3177-83.
The gaseous photocatalytic degradation of dibenzofuran, dioxins-like substance, was investigated by using TiO2, Ce3+/TiOs and Fe3+/TiO2 as photocatalysts. The batch-type photocatalytic reaction experiments were conducted, and the effects of initial concentration of reactant, humidity, circulation flow rate and light intensity on the photocatalytic degradation of dibenzofuran were studied. And the models and methods for estimating photocatalytic reaction constants and Langmuir adsorption constants were proposed. Results showed that the photocatalytic activity of the TiO2 photocatalyst was obviously improved after doping with Fe3+ and Ce3+, and the photocatalytic activity of Fe3+/TiO2 was the best in three photocatalysts. The degradation rate of dibenzofuran increased with the increase of the initial concentration of gaseous dibenzofuran in the batch-type photocatalytic reaction system. The photocatalytic degradation of gaseous dibenzofuran was enhanced when proper quantities of water vapor existed. However, it would be inhibited if there was excessive water vapor. As the circulation flow rate and the light intensity increased, the photocatalytic degradation rate of gaseous dibenzofuran also increased. The photocatalytic reaction rate coefficients of dibenzofuran on the photocatalysts TiO2, Ce3+/TiO2 and Fe3+/TiO2 were 34.54 x 10(-5), 36.23 x 10(-5) and 37.95 x 10(-4) mg x (min x m2)(-1) respectively.
以TiO₂、Ce³⁺/TiO₂和Fe³⁺/TiO₂为光催化剂，研究了二苯并呋喃（二噁英类物质）的气相光催化降解。进行了间歇式光催化反应实验，研究了反应物初始浓度、湿度、循环流速和光照强度对二苯并呋喃光催化降解的影响。并提出了估算光催化反应常数和朗缪尔吸附常数的模型和方法。结果表明，掺杂Fe³⁺和Ce³⁺后TiO₂光催化剂的光催化活性明显提高，Fe³⁺/TiO₂在三种光催化剂中光催化活性最佳。在间歇式光催化反应体系中，二苯并呋喃的降解率随气态二苯并呋喃初始浓度的增加而增大。适量水蒸气存在时气态二苯并呋喃的光催化降解增强。然而，如果水蒸气过量则会受到抑制。随着循环流速和光照强度的增加，气态二苯并呋喃的光催化降解率也增加。二苯并呋喃在光催化剂TiO₂、Ce³⁺/TiO₂和Fe³⁺/TiO₂上的光催化反应速率系数分别为34.54×10⁻⁵、36.23×10⁻⁵和37.95×10⁻⁴mg·(min·m²)⁻¹。
