摘要
以土壤为介质,菲(Phe)、芘(Pyr)和苯并[a]芘(BaP)为目标污染物,研究了纳米TiO_2和Fe_2O_3为催化剂下,紫外辐射强度对光催化降解多环芳烃及动力学参数的影响。结果表明,随着辐射强度的增加,光催化降解PAHs的速率常数增加,半衰期缩短。当辐射强度从527μW·cm-2增加到1071μW·cm-2,纳米TiO2催化下,BaP光催化降解速率常数从0.0053h-1增加到0.0078h-1,Pyr降解速率常数从0.0017h-1增加到0.0037h-1,Phe降解速率常数从0.0039h-1增加到0.0060h-1;Fe2O3催化下,BaP光催化降解速率常数从0.0049h-1增加到0.0069h-1,Pyr降解速率常数从0.0016h-1增加到0.0036h-1,Phe降解速率常数从0.0038h-1增加到0.0053h-1。随辐射强度的增加,Pyr的光催化降解的速率常数和半衰期变化最大。
This paper studied the photocatalytic degradation of phenanthrene (Phe), pyrene (Pyr) and benzo[a]pyrene (BaP) in soil as target contaminants and its dynamics using nano-TiO2 or Fe2O3 as catalyst under different UV radiant intensities. The results show that the photo- catalytic degradation rates of the three PAHs (polycyclic aromatic hydrocarbons) increase with the increase of UV irradiation intensity, but the half-life of photocatalytic degradation is decreased. As UV radiant intensity increases from 527 to 1 071 μW·cm^-2 using nano-TiO2 as catalyst, the photocatalytic degradation rate of BaP increases from 0.005 3 h^-1 to 0.007 8 h^-1, Pyr increases from 0.001 7 h^-1 to 0.003 7 h^-1, and Phe increases from 0.003 9 h^-1 to 0.006 0 h^-1, while, using Fe2O3 as catalyst, the photoeatalytic degradation rates of BaP, Pyr and Phe increase from 0.004 9 h^-1 to 0.006 9 h^-1, from 0.001 6 h^-1 to 0.003 6 h^-1, and from 0.003 8 h^-1 to 0.005 3 h^-1 respectively. Of the three contaminates, the photocatalytic degradation rate and half-life of photocatalytic degradation of Pyr vary most greatly with the increase of radiant intensity.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2008年第5期1711-1715,共5页
Journal of Agro-Environment Science
基金
中科院知识创新工程重大项目kzcx1-yw-06-03
国家重点基础研究发展计划(2004CB418506)
国家高技术研究发展计划(863)项目(2007AA061101)
关键词
辐射强度
土壤
PAHS
光催化降解
动力学
radiant intensity
soil
PAHs
photocatalytic degradation
dynamics