VUV photolysis of naphthalene in indoor air: Intermediates, pathways, and health risk.
VUV photolysis of naphthalene in indoor air: Intermediates, pathways, and health risk.
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DOI：
10.1016/j.chemosphere.2013.01.086
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发表时间：
2013-05
期刊：
影响因子：
8.8
通讯作者：
Weirong Zhao;Yanan Yang;Jiusong Dai;Feifei Liu;Y. Wang
中科院分区：
文献类型：
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作者：
Weirong Zhao;Yanan Yang;Jiusong Dai;Feifei Liu;Y. Wang
为评价真空紫外线(VUV)光解室内空气中萘(NP)的健康风险，采用气相色谱-质谱仪(GC-MS)和质子转移反应-质谱仪对中间产物进行了检测。结果表明，气相中有13种挥发性有机化合物(VOCs)，油相中有5种半挥发性有机化合物(SVOCs)。NP的VUV光解途径可分为功能化、分配、缩合、裂解和矿化五个阶段。最初，NP通过氧化自由基的官能化作用转化为几种SVOCs。具有高沸点和极性基团的SVOCs会在气溶胶和气相之间进行分配。气溶胶相中一定量的SVOCs通过冷凝转化为油性物质，可通过湿式洗涤器等常规洗涤技术将其洗出。气相中的大部分SVOCs通过裂解转化为VOCs，VOCs可进一步矿化为CO2。VUV照射2.81min后，VOCs尤其是高危害性醛的积累导致健康风险影响指数(η)增加到150%，而VOCs的矿化作用导致η急剧下降，在7.01min后降至28。由此可见，VOCs的矿化是缓解光解健康风险的关键因素。研究结果将为VUV光解技术在室内空气净化中的安全、经济应用提供指导。
To evaluate the health risk of vacuum ultraviolet (VUV) photolysis of naphthalene (NP) in indoor air, intermediates were detected by gas chromatograph–mass spectrometry and proton transfer reaction-mass spectrometry. Results showed that 13 volatile organic compounds (VOCs) in gas phase and five semi-volatile organic compounds (SVOCs) in oil phase were the main intermediates. VUV photolysis pathways of NP can be divided into five stages including functionalization, partition, condensation, fragmentation, and mineralization. Initially NP was converted into several SVOCs via functionalization by oxidative radicals. SVOCs with high boiling points and polarity groups would partition between aerosol and gas phase. Certain amount of SVOCs in aerosol phase were transformed to oily substances by condensation, which can be washed out by conventional gas washing technique like wet scrubber easily. A majority of SVOCs in gas phase were converted to VOCs by fragmentation, which can be further mineralized into CO2. The accumulation of VOCs, especially highly harmful aldehydes, resulted in an increase of health risk influence index (η) to 150 after VUV irradiation of 2.81min, while the mineralization of VOCs led to a sharp decline of η to 28 after VUV irradiation of 7.01min. It can be concluded that the mineralization of VOCs is a key factor to alleviate the health risk of photolysis. The results will guide a safe and economical application of VUV photolysis technology in indoor air purification.