Quantification and risk assessment of organic products resulting from non-thermal plasma removal of toluene in nitrogen

Teng Guo; Xubing Du; Zhen Peng; Li Xu; Junguo Dong; Jianquan Li; Ping Cheng; Zhen Zhou

doi:10.1002/rcm.7917

Quantification and risk assessment of organic products resulting from non-thermal plasma removal of toluene in nitrogen

Rapid Commun Mass Spectrom. 2017 Sep 15;31(17):1424-1430. doi: 10.1002/rcm.7917.

Authors

Teng Guo¹, Xubing Du², Zhen Peng³, Li Xu¹, Junguo Dong¹, Jianquan Li², Ping Cheng¹, Zhen Zhou³

Affiliations

¹ School of Environmental and Chemical Engineering, Shanghai University, Shanghai, 200444, China.
² School of Instrument Science and Opto-electronics Engineering, Hefei University of Technology, Hefei, 230009, China.
³ Institute of Environment Safety and Pollution Control, Jinan University, Guangzhou, China, 510632.

PMID: 28586540
DOI: 10.1002/rcm.7917

Abstract

Rationale: 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.

Methods: 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.

Results: 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.

Conclusions: 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.