Online pretreatment method and online pretreatment device of SVOCs (Semi Volatile Organic Compounds) in water

Abstract

The invention discloses an online pretreatment method and an online pretreatment device of SVOCs (Semi Volatile Organic Compounds) in water. A water sample circulates to carry out contact adsorption with a fixed extracting rod by using an online pulse extraction technology, so that the competitive adsorption of the surface of a stirrer on the sample in solid phase microextraction of fiber is avoided, and the extracting rod is prevented from colliding with a container, thus the service life is prolonged. On the basis of the method, the invention also provides the online pretreatment device of the SVOCs in water, which can be used for realizing procedures of fully-automatic sampling, sampling matching, adsorptive enrichment, analysis and self-washing of a flow passage as well as intermittent pretreatment of the SVOCs in the water sample and is very suitable for online pretreatment of the SVOCs in the water.

Description

technical field [0001] The invention relates to the technical field of on-line monitoring instruments, in particular to an on-line pretreatment method and device for SVOCs in water. Background technique [0002] Semi-volatile organic compounds (SVOCs) are a class of pollutants that widely exist in the environment, and their concentrations in surface water are very low, but the impact of these trace organic compounds on the ecological environment and human health cannot be ignored. Therefore, rapid and accurate qualitative and quantitative analysis of it has always been the frontier field of sanitation inspection, and it is the premise of grasping the organic pollution status of surface water and controlling the discharge of organic pollutants. [0003] At present, the national standard methods for semi-volatile organic compounds in water in my country's environmental monitoring and law enforcement are not comprehensive enough. The method of measuring SVOCs is usually to clas...

AI Technical Summary

Problems solved by technology

However, the sample enrichment efficiency is not high, and further concentration treatment is required after solvent rinsing, so it is difficult to realize online

Compared with solid-phase extraction cartridges, solid-phase extraction membrane discs can further shorten the extraction time, but the extraction membrane is a one-time consumable and needs to be replaced after use, making it more difficult to achieve automated online pre-treatment

The amount of adsorbed stationary phase in a conventional fiber needle solid phase microextractor is 1 μL, which limits the extraction enrichment factor and cannot meet the requirements of many trace analysis; in addition, although the existing instruments can achieve sequential continuous processing, the operation process still uses manual The offline operation mode of sampling and sample preparation is difficult to ensure the repeatability of the analysis results, and is not suitable for the automatic pretreatment of SVOCs on site; the life of the extraction fiber in the extractor is short (less than 30 times), which also increases the analysis cost

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