Photocatalytic degradation of typical semi-volatile organic compounds in indoor environments
ZHU Yu-jie1, LIU Bi-yuan1, GE Hao-nan1, DUAN Xing-yu1, CAO Jian-ping1, HUANG Hai-bao1,2
1. School of Environmental Science and Engineering, SunYat-sen University, Guangzhou 510006, China; 2. Chemical Engineering Institute, Xinjiang University, Urumqi 830017, China
Abstract：Semi-volatile organic compounds (SVOCs) can be easily adsorbed by indoor surfaces and thus are difficult to be removed by ventilation or air purification. Photocatalytic oxidation technology has bright prospects in the field of indoor air purification, but its performance on removing indoor SVOCs is still unclear. In this study, we found that the commonly-used photocatalyst (P25titanium dioxide) could effectively degrade two typical indoor SVOCs (dibutyl phthalate (DnBP) and tri (2-chloropropyl) phosphate (TCPP)) under the irradiation of both a 254 nm ultraviolet lamp and a fluorescent lamp, and the degradation process could be described by the first-order kinetic equation. Under the irradiation of fluorescent lamp, DnBP and TCPP were completely degraded within 120 and 42h, respectively, being significantly faster than the removal rate of ventilation and air purification for these two SVOCs. Furthermore, the degradation products and corresponding pathways of DnBP and TCPP were analyzed by gas chromatography-mass spectrometry coupled with proton transfer reaction time-of-flight mass spectrometer.
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