光催化降解室内气相甲醛的光强研究  

STUDY ON LIGHT INTENSITIES OF PHOTOCATALYTIC DEGRADATION OF INDOOR GASEOUS FORMALDEHYDE

作　　者：杨莉萍[1] 刘震炎[1] 施建伟[1] 上官文峰[1] 

机构地区：[1]上海交通大学机械动力工程学院,上海200030

出　　处：《太阳能学报》2007年第7期689-694,共6页Acta Energiae Solaris Sinica

基　　金：上海市科技发展基金资助项目(022312146)

摘　　要：分析了光催化过程中的光能损失,基于羟基自由基是降解挥发性有机物的主要氧化物种的假设提出了确定合适的光强来节约光能的方法,在假设电子空穴对完全利用的基础上定义了过量系数,并根据负载TiO2的玻璃平板反应器和泡沫镍反应器降解甲醛的实验数据确定了所需合适的光强和过量系数。结果表明:该方法能确定合适的光强,其降解性能好和光能利用率高。对于负载在玻璃平板上的TiO2,降解85.89μmol/m3(2.1ppm)的甲醛所需合适的光强为0.33mW/cm2(352nm),过量系数为1.33;对于负载在泡沫镍网上的TiO2,降解81.8μmol/m3(2ppm)的甲醛所需合适的光强为0.25mW/cm2(254nm),过量系数为1.39。Light energy losses in heterogeneous photocatalysis processes were analyzed. A method of determining appropriate light intensities for saving energy was presented in the light of hydroxyl radicals being the primary reactants in the degradation of volatile organic compounds and an excess coefficient of light intensity was defined base on the assmnption of complete utilization of excited electron-hole pairs. Excess coefficients and appropriate light intensities for degrading indoor gaseous formaldehyde were determined according to the data from a titania-coated glass plate reactor and a titania-coated reticular foam nickel reactor. The results showed that appropriate light intensities could be derived according to our method and good degradation performance and high utilization ratio of light energy could be attained simultaneously. For the titania-coated glass plate reactor, the appropriate light intensity was 0.33mW/cm^2 （352nm） and the excess coefficient was 1.33 for degrading 2. lppm formaldehyde. For the titania-coated reticular foam nickel reactor, the appropriate light intensity was 0.25mW/cm^2 （254nm） and the excess coefficient was 1.39 for degrading 2ppm formaldehyde.

关 键 词：光催化氧化 气相甲醛 能量损失 光强 

分 类 号：TK511.4[动力工程及工程热物理—热能工程]