不同有机化合物在TiO_2负载活性炭纤维上的光降解-分子尺寸的影响(英文)  

Photodegradation of organic compounds over TiO_2 supported on activated carbon fibers: the effect of molecular size

作　　者：员汝胜[1] 吴保朝[1] 王占义[1] 王绪绪[1] 

机构地区：[1]福州大学光催化研究所,福建福州350002

出　　处：《工业催化》2007年第12期52-57,共6页Industrial Catalysis

基　　金：国家自然科学基金(青年,20701008);教育部科学技术研究重点项目(207053);福建省自然科学基金(E0610011)

摘　　要：以环氧树脂为炭质前驱体将TiO2粉体粘附于ACF表面,然后在N2气氛460℃焙烧,树脂热解、逸失使剩余残炭成为二者之间的连接体,获得TiO2/ACF复合产品。ACF负载TiO2后,其比表面积降低,但仍很好地维持了ACF的孔隙结构。由SEM可知,纳米级单体TiO2颗粒以微小团簇结构分布于ACF表面。以对氨基苯酚、亚甲基兰和β-环状糊精三种不同分子尺寸的有机化合物为探针,通过TiO2/ACF对它们的光催化降解研究发现,化合物自身分子尺寸对其降解程度有重要影响。具有适宜分子尺寸亚甲基兰的去除程度最高,TiO2/ACF的降解速率高于悬浮态P25,在重复利用过程中未见降低。通过对比三种有机分子在有、无紫外光照下的去除程度,可确认有机分子是被降解而非吸附于TiO2/ACF上。TiO2 was supported on activated carbon fibers （ACF） with utilization of epoxy resin as the precursor of adhesive coating, followed by calcination at 460 ℃ in nitrogen atmosphere. As TiO2 was loaded on ACF, the specific surface area of the supported catalyst （TiO2/ACF） decreased, but the pore structure of ACF was well preserved. From SEM images, it was observed that TiO2 distributed on ACF in the form of small clusters with the size of primary particles in nanometer. The photocatalytic degradations of three organic compounds with different molecular sizes, i.e. p-aminophenol, methylene blue and β-cyclodextrin were investigated. The results showed that the molecular size of organic compound had an important effect on its degradation over TiO2/ACF catalyst. The highest efficiency of degradation can be obtained only when methylene blue molecules with moderate size was employed in the reaction. Furthermore, the rate of photodegradation was higher than that when the suspended P25 was used as photocatalyst without any decline for repeating use. By comparison the amounts of three organic compounds removal with and without UV irradiation, it was confirmed that the compounds were degraded instead of being adsorbed on TiO2/ACF.

关 键 词：TIO2 活性炭纤维 光催化 分子尺寸 

分 类 号：TE624.4[石油与天然气工程—油气加工工程]