环境温度湿度对TiO_2/ACF光催化净化甲苯的影响  

Influence of Environmental Temperature and Relative Humidity on Photocatalytic Oxidation of Toluene Using Activated Carbon Fibers Coated TiO_2

作　　者：郭婷[1] 白志鹏[1] 吴灿[1] 朱坦[1] 

机构地区：[1]南开大学环境科学与工程学院国家环境保护城市空气颗粒物污染防治重点实验室,天津300071

出　　处：《城市环境与城市生态》2007年第5期10-13,共4页Urban Environment & Urban Ecology

基　　金：国家教育部"跨世纪优秀人才培养计划"基金(2002-48);教育部留学回国人员科研启动基金(2003-406);2006年天津市科技发展计划攻关培育项目(2006-38)

摘　　要：吸附型光催化剂TiO2/ACF是近年来净化室内空气的新材料。为弄清TiO2/ACF光催化净化甲苯的最佳环境温度湿度,研究了环境温度湿度对气相甲苯在TiO2/ACF上平衡吸附及对吸附态甲苯光催化净化效果的影响,评估了不同温度湿度条件下TiO2/ACF的甲苯净化能力。研究发现,尽管高温高湿有利于吸附态甲苯的光催化去除,但与此同时也抑制了甲苯在TiO2/ACF表面的富集吸附。定量分析甲苯光催化降解的中间产物,结果显示,中间产物的积累量随环境温度的升高而显著增加;环境湿度增大,虽然支链中间产物的积累量减小,但毒性更强的苯环氧化中间产物却逐渐增加,说明在高温高湿条件下进行甲苯光催化降解具有更高的环境二次污染风险。总之,环境温度湿度的改变对吸附-光催化的协同净化能力既有促进作用又有负面作用,在多相光催化技术实际应用过程中,只有控制适宜的环境温度湿度,才能保障该技术在空气净化领域快速、高效且安全地应用。在本实验体系下,环境温度25℃,相对湿度30%是甲苯净化的最佳条件。TiO2 /ACF,an absorbable photocatalyst,is a new kind of material applied in the air purification.To explore the optimal temperature and humidity for purifying toluene with the photocatalytic oxidation on the TiO2 /ACF,the influence of environmental temperature(T) and relative humidity(RH) on the gas-solid adsorption of toluene and the photocatalytic oxidation(PCO) efficiency of adsorbed toluene on TiO2 /ACF were researched by this thesis,and then,the purification capability of TiO2 /ACF was estimated.PCO results showed that although the PCO efficiency increased under high RH and T levels,the adsorption of toluene decreased.Moreover,the quantitative results of the intermediates indicated that when PCO of toluene were carried out at high environmental T and RH levels,more environmental risk emerged for more toxic intermediates would be accumulated on the TiO2 /ACF.So,it was significant to control the environmental T and RH conditions in the application of the PCO technique.T=25℃ and RH=30% were the optimal conditions for purifying toluene in the experimental system.

关 键 词：环境温度 相对湿度 TIO2/ACF 光催化氧化 甲苯 

分 类 号：X51[环境科学与工程—环境工程]