The Research In Method Of The Determination Of SVOCs In Air Enriched By Ionic Liauid With Auto Thermal Desorption-gas Chromatography-mass Spectrometry

The room temperature ionic liquids have become one of the hotspots in researchof green chemistry based on its characteristics of lower vapor pressure, higher ionicstrength and better solubility. In this study, ionic liquids were used to adsorb thephthalic acid esters (PAEs) and polybrominated diphenyl ethers (PBDEs) in indoor air,and the adsorption effect was studied.Five phthalic acid esters（DMP、DEP、DBP、BBP、DEHP）and twopolybrominated diphenyl ethers (PBDE-28、PBDE-47) have been studied in this paper.And the detection method of ATD-GC/MS was established. Two sampling methodswhich were active and passive were designed according to the characteristic of theresearch objects, and the sampling conditions were optimized. In addition, the effectof the enrichment was compared among the1-butyl-3-methyl imidazoliumhexafluorophosphate ([BMIM]NTF2)、Tenax and [CH2COOMeMIM]NTF2whichwere synthetized by our laboratory. Finally [CH2COOMeMIM]NTF2was chosen asthe enrichment material with the active sampling method. The mass ratio between theionic liquid and the white support was15%, and the sampling flow was1L/min witha sampling time of90min;2-stage desorption mode was adopted when the sampleswere determined, one of which was tube desorption with a desorption temperature of280℃, a desorption time of15min and a desorption flow of50mL/min; the other wascold trap desorption, the low trap temperature was0℃and the high trap temperaturewas280℃, the heat rate was40℃/s, in addition, the heated valve temperature was230℃and the transfer line temperature was280℃, furthermore, there was no inletsplit or outlet split; the conditions of the GC/MS are as follows:Firstly, kept the initialtemperature of100℃for1min and then rose it to200℃with the rate of10℃/min,subsequently, reduced the rate for6℃/min until250℃and kept for10min. Therecoveries of standard additions for this method were in the range of97.13%to113.8%with a detection limit of0.3~1ug/L and the relative standard deviation (RSD)was between3.337%and9.932%.Practical indoor air samples which were collected from ten offices in Beijingwere analyzed in this paper. Four kinds of pollutant were mainly detected includedDMP, DEP, DBP and DEHP. The DBP and DEHP pollutants were the most serious. The result shows that ionic liquid can be used as an enriched materials of SVOCs,which expands the application field of the ionic liquids.