TiO_2对香烟烟气中PAHs的光催化降解

Photocatalytic degradation of PAHs in cigarette smoke catalyzed by TiO_2

利用自行组装的烟气采集装置,研究了TiO2对香烟烟气中多环芳烃(PAHs)光催化降解的效果.运用气质联用仪,对烟气中的多环芳烃进行分析,结果表明TiO2和光对多环芳烃光降解效果随环数变化有不同的变化趋势,TiO2的量是决定低环多环芳烃降解效率的主要因素;紫外辐射强度是决定高环多环芳烃降解效果的主要因素.在弱紫外辐射条件下,TiO2的量由3g增加到6g时,低环多环芳烃降解效率提高38.7%;在固定TiO2为3g时,紫外辐射强度增强1倍使高环多环芳烃降解效率提高87.2%;在强紫外辐射条件下,TiO2的使用会降低低环多环芳烃的光催化降解效率,TiO2分别为3g和6g时,低环多环芳烃降解效率分别下降76.9%和72.4%;在3gTiO2条件下,苯并[a]芘的催化降解效果最好,效率提高83.5%.

Gas sampling installations assembled by ourselves were used to study photocatalytic degradation of polycyclic aromatic hydrocarbons（PAHs） in cigarette smoke.PAHs in the samples were analyzed by gas chromatography with mass selective detection.Results show that the photocatalytic degradation effect of low-ring PAHs was determined by quantity of TiO2,while the photocatalytic degradation effect of high-ring PAHs was determined by intensity of UV-C light.Under weak UV-C light,photocatalytic degradation efficiency of low-ring PAHs increased by 38.7% with the amount of TiO2 increased from 3 grams to 6 grams.Under the amount of 3 grams of TiO2,the photocatalytic degradation efficiency of high-ring PAHs increased by 87.2% when UV-C light intensity was enhanced.However,under strong UV-C irradiation,the catalytic degradation efficiency of low-ring PAHs decreased by 76.9%（under 3 grams of TiO2） and 72.4%（under 6 grams of TiO2）.Under the amount of 3 grams of TiO2 with strong UV-C irradiation,the catalytic degradation efficiency of B[a]P increased by 83.5%.