Guo Teng, Du Xubing, Peng Zhen, Xu Li, Dong Junguo, Li Jianquan, Cheng Ping, Zhou Zhen
School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China.
School of Instrument Science and Opto-electronics Engineering, Hefei University of Technology, Hefei, 230009, China.
Rapid Commun Mass Spectrom. 2017 Sep 15;31(17):1424-1430. doi: 10.1002/rcm.7917.
Non-thermal plasma (NTP) has proven to be an effective approach for the removal of volatile organic compounds (VOCs). However, harmful organic by-products, produced during NTP-mediated removal of VOCs, hinder practical applications of this technology. It is necessary to characterize the organic by-products to assess their health risks.
A method is proposed for analyzing and evaluating organic by-products for NTP-mediated removal of VOCs in this work. NTP generated by a coaxial dielectric barrier discharge (DBD) reactor was used for the removal of a model VOC, toluene, in nitrogen. Organic products were characterized using a real-time proton transfer reaction time-of-flight mass spectrometry (PTR-TOF-MS) apparatus.
The PTR-TOF-MS apparatus has been shown to be effective for real-time high-sensitivity detection of trace VOCs. The main observed organic compounds, with concentrations on the order of ppb/ppm, were hydrogen cyanide, acetonitrile, propanenitrile, benzene, benzonitrile, and benzyl nitrile, etc.
A health-related index (HRI) was introduced to assess the health risks associated with these organic products. The HRI was not correlated with the removal efficiency (η), with higher η possibly yielding higher HRI, associated with higher health risks. Specific input energy (SIE) was a key factor affecting the formation of the observed organic products and their HRI values. We conclude that in practical applications, SIE, HRI, and η must be balanced.
非热等离子体（NTP）已被证明是一种去除挥发性有机化合物（VOCs）的有效方法。然而，在NTP介导的VOCs去除过程中产生的有害有机副产物阻碍了该技术的实际应用。有必要对有机副产物进行表征以评估其健康风险。
本文提出了一种分析和评估NTP介导的VOCs去除过程中有机副产物的方法。使用同轴介质阻挡放电（DBD）反应器产生的NTP在氮气中去除模型VOC甲苯。使用实时质子转移反应飞行时间质谱仪（PTR-TOF-MS）对有机产物进行表征。
PTR-TOF-MS仪器已被证明对痕量VOCs的实时高灵敏度检测有效。观察到的主要有机化合物，浓度在ppb/ppm量级，有氰化氢、乙腈、丙腈、苯、苯甲腈和苄腈等。
引入了一个与健康相关的指数（HRI）来评估与这些有机产物相关的健康风险。HRI与去除效率（η）无关，η越高可能产生越高的HRI，意味着健康风险越高。比输入能量（SIE）是影响观察到的有机产物形成及其HRI值的关键因素。我们得出结论，在实际应用中，必须平衡SIE、HRI和η。
