Application of Membrane Inlet/Time-of-Flight Mass Spectrometry for Online Monitoring of Volatile Organic Compounds in Water and Early Warning of Source Water Pollution Accident

摘要

For constructing a monitoring and early-warning system of source water pollution accident, membrane inlet/time-of-flight mass spectrometry was applied to the online monitoring of some typical volatile organic compounds. The results show that the system responds quickly to benzene hydrocarbons (30-70 s) and halogenated aliphatic hydrocarbons (30 s); the linear range is 3-4 magnitudes; the detection limits of benzene hydrocarbons and chlorobenzene are less than 10 ppb. Thirty days' continuous monitoring indicates that the system is stable (relative standard deviation < 5%); the accuracy is acceptable (relative error is 28.7% and can be reduced to within 10% by periodical calibration). The system is proven to be available for the monitoring and early-warning of source water pollution accident.