Atmospheric pollutant real-time sampling and analysis device and method

Abstract

The invention provides an atmospheric pollutant real-time sampling and analysis device and a method. The device comprises a particulate matters online sampling unit, an environment gas component sampling unit, a soft ionization device and a mass spectrometer; the particulate matters online sampling unit comprises an atmosphere intake pipeline, a rotary table component, a first gas guiding flexiblepipe, a sucking pump, a film heating component, a first three-way valve and a nitrogen high pressure bottle. The device and the method provided by the invention have the following advantages: (1) reactive ions with relatively high reaction activity are generated through plasmas, the reactive ions react with a compound desorbed from a sampling film, thus, analyzable sample range of the device is expanded, and method sensitivity is improved; a sample is enabled to pass through a plasma generation device, contact area and time between the sample and the plasmas can be improved, and efficiency isimproved; (2) a plurality of particulate matters sampling films are mounted on the rotary table, thus, frequency of halting and changing the films is reduced, sample collection efficiency is improved, and operation steps are simplified; (3) the particulate matters sampling films are directly heated through a honeycomb window, and particulate state sample thermal desorption efficiency is improved.

Description

technical field [0001] The invention belongs to the technical field of air pollution detection, and in particular relates to a device and method for real-time sampling and analysis of air pollutants. Background technique [0002] Chemical analysis of complex compounds in air pollutants requires powerful tools. Mass spectrometry is a method for identifying the elemental composition of a compound by measuring its molecular weight, and then analyzing its structure. It has the characteristics of high sensitivity and universality, so it is especially suitable for the analysis of air pollutants. For particulate pollutants, the off-line mass spectrometry method based on membrane sampling is widely used now, that is, the particulate matter is collected on the filter membrane for 12-24 hours, the soluble matter is extracted with a solvent, and then undergoes complex pretreatment, and finally passes through chromatography. - Analyzed by mass spectrometry. Although this method can de...

AI Technical Summary

Problems solved by technology

There are three main problems in this method: First, although the chemical ionization source belongs to the soft ionization source, which is helpful for the identification of the compound, the type of sample that can be ionized is limited by the type of chemical reaction gas used, and its versatility is not strong. Cannot ionize all contaminants

2. Since the PTFE sampling membrane is not resistant to high temperatures, it can only dissociate particulate pollutants with a lower boiling point, and there is only one membrane in the device, and repeated use in a short period of time may cause the results of each analysis to be mutually exclusive. interference

3. The compound in the sampling membrane is desorbed and diluted by a large flow of hot nitrogen gas, which reduces the sensitivity of the instrument

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