Application Of QuEChERS-Gas Chromatography-Mass Spectrometry Method In The Identification Of Typical SVOCs In Solid Waste

In recent years,the pollution to the environment and the harm to the human health caused by solid waste are increasing day by day.The detection of organic pollutants in solid waste becomes a research hotspot which has been included in the 13th Five-Year plan of the National Environmental Protection Standards.The criteria for the identification of organic pollutants in solid waste in China mainly include GB 5085.3-2007,HJ 951-2018,HJ 834-2017 and so on,while the identification technology is not mature enough.It is essential to develope new methods and technologies for the identification of organic compounds in solid waste.This study focused on the pretreatment of samples and the methods of analysis.Based on the main semi volatile organic compounds?SVOCs?categories in GB 5085.3-2007,8 typical SVOCs with 88 targets were selected,aiming to establish a reliable method for high-throughput and rapid identification of SVOCs in solid waste,which can provide technical support for the identification of organic pollutants in solid waste in China.Establishment and optimization of the method.The detection effects of the targets under different influencing factors were discussed from the aspects of pretreatment methods and analysis methods,and a suitable detection method was established.The gas chromatography-mass spectrometry?GC-MS?analysis method was as follows:The seperation was performed on a capillary column?HP-5MS UI,30m×0.25mm×0.25?m?.The solvent delay time was set for 4min.The samples were injected under pulse splitless mode for 1min.The column temperature started at 50°C,kept for 2min,rose to 66°C at the rate of 5°C/min,rose to 80°C at the rate of 25°C/min,rose to 270°C at the rate of 5°C/min,then rose to 290°C at the rate of25°C/min,and kept for 4min.The injector temperature was 270?and the interface temperature was 300?.During the sample preparation,dichloromethane was selected as extraction solvent,MgSO₄,NaCl,C₆H₅Na₃O₇·2H₂O and C₆H₆Na₂O₇·1.5H₂O were selected as phase partiton salts,primary secondary amine?PSA?,C₁₈ and MgSO₄ were selected as cleanup sorbents,and the solution to be tested was concentrated by nitrogen blowing instrument.Verification of the method.Under the blank monitoring,the sensitivity,linear range,precision,accuracy and matrix effect of the method were confirmed,and the samples were detected as the means of auxiliary verification.The linear correlation coefficients were0.9961-0.9999 in the linear ranges of 2?g/kg-2800?g/kg.The limits of detection?LODs?ranged from 0.18?g/kg to 4.5?g/kg with the limits of quantification?LOQs?in the range of0.59?g/kg-15?g/kg.The recoveries of the targets were 45.3%-117%at three spiked concentration levels.The relative standard deviations?RSDs?were 1.2%-14%?n=6?.Compared with related standards,this method is more sensitive,and the linearity,precision and accuracy could meet the requirements of the standards.The recoveries of the targets in the actual samples were 41.0%-129%,and the relative standard deviations were 1.8%-29%?n=6?,which proved the feasibility and practicability of the method.This study established a QuEChERS-gas chromatography-mass spectrometry method that can quickly identify 88 SVOCs in solid waste.It can be applied to the detection of SVOCs in typical solid waste and the improvement of 7 existing standards,providing new ideas for the identification of SVOCs in solid waste.