膜进样/飞行时间质谱实时分析水源水中挥发性有机污染物

Realtime Analysis of Volatile Organic Compounds in Source Water by Membrane Inlet/Time-of-Flight Mass Spectrometry

为建立饮用水源地污染事故监控预警系统,采用膜进样/飞行时间质谱技术,对苯系物、取代苯、卤代烷等典型挥发性有机物模拟事故状况下的污染水体进行了在线监测。研究结果表明,该技术对目标有机污染物的响应时间短,对苯系物为30～70s、对卤代烷为30s,线性检测范围达到3～4个数量级,苯系物和氯苯的检测限小于10μg.L-1,满足污染物实时监测分析的要求。连续30天、总计52次模拟水污染事故的在线监测表明,该技术稳定性强,平均波动小于5%,定期校准可使平均相对误差控制在10%以内,适用于饮用水源地挥发性有机污染事故的远程监控预警。

To establish an early-warning system for source water pollution accident,a membrane inlet / time-of-flight mass spectrometry technology was applied to a series of pollution scenarios as an online monitoring method for typical volatile organic compounds such as BTEX（benzene,toluene,ethylbenzene and xylene）,substituted benzenes,and halogenated aliphatic hydrocarbons.It was shown that this technology can adequately meet the requirements of realtime analysis with short response time to the target organic pollutants（30~70 s for BTEX and 30 s for halogenated aliphatic hydrocarbons） in a linear detecting range of 3~4 magnitudes;the detection limits of BTEX and chlorobenzene were less than 10 μg·L-1.The results of 52 simulated water pollution accidents in a 30-days＇ continuous monitoring indicated that the monitoring system was stable with the relative standard deviation less than 5%;the accuracy was acceptable and could be reduced to within 10% by periodical calibrations.Membrane inlet/time-of-flight mass spectrometry technology was proven to be available for the remote monitoring and early-warning of source water pollution accident.