Method for enriching and separating trace amount of polychlorinated biphenyls (PCBs)

Abstract

The invention relates to a method for enriching and separating a trace amount of polychlorinated biphenyls (PCBs). According to the method, a trace amount of the PCBs in an environmental sample are enriched by a modified solid-phase microextraction column by a combining a method that a trace amount of the PCBs are subjected to linkage separation by a double column gas chromatography-electron capture detector, and then are eluted and detected. Compared with the prior art, the method has the advantages that: a macromolecule fixed phase of the solid-phase microextraction column is modified, a solid-phase microextraction technology is combined with the gas chromatography-electron capture detector, sampling, extraction, concentration, sample separation, and detection are combined into a simpleprocess, automaton is easy to realized, the amount of the pre-enriched samples and the detection time are reduced, and the effect of enriching the PCBs is improved; the nature is determined by a double chromatographic column, and PCB monomers with different polarities and structures are separated; the method has the advantages of high analysis speed, low manufacturing cost, and high detection sensitivity and specificity and the like, and is easy to operate; instruments are portable; and the detection limit of the coplanar PCB monomers in water can reach 10<-8> to 10<-7> mol / L, and the field test of residues of toxication forms of six kinds of main PCBs can be realized.

Description

technical field [0001] The invention relates to the field of environmental detection, specifically adopting a modified solid-phase microextraction column to enrich trace polychlorinated biphenyls (PCBs) in water, and combining gas chromatography-electron capture detector (gas chromatography-electronic capture detector) after elution capture detector) to detect various PCBs monomer methods and solid-phase microextraction devices. Background technique [0002] Early analysis of polychlorinated biphenyls (PCBs) followed the chemical analysis methods of organochlorine pesticides in the 1960s, including colorimetry, thermal analysis, and chemical titration. At present, the analysis of PCBs monomer mainly uses gas chromatography-electron capture detector (gas chromatography-electron capture detector), gas chromatography / mass spectrometer (including: GC-MS, multistage mass spectrometry, selective ion detection method, multi-ion detection method and negative ion chemical ionization...

AI Technical Summary

Problems solved by technology

[0005] (1) A large amount of organic solvents are required, causing secondary pollution and endangering the environment and human health

[0006] (2) Some traditional extraction methods are time-consuming and labor-intensive, reducing analysis efficiency

[0007] (3) The problem of emulsification occurs, prolonging the extraction time

[0008] (4) Interference peaks are generated, resulting in changes in the peaks of the analyte and reduction in column efficiency

[0009] (5) The injected extract sometimes reduces the sensitivity of the detector and shortens the life of the column

At present, in this field of technology, the use of the present invention to detect organic monomers has not yet been reported.

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