Studies On Analysis And Detection Methods Of Perfluorinated Compounds And Dioxins

As fluorine chemical industry important chemical products,perfluorinated compounds are widely used in daily life and the industry.Dioxins is a kind of persistent organic pollution that are unintentionally produced by humans.Both of the said organics have brought huge harmness to human health and the environment.Therefor,establishing appropriate detection method for the quality control is our first important task at present.The research status at home and abroad about the physical and chemical nature of perfluorinated compounds and dioxins was reviewed and the perfluorinated carboxylic acid compounds in soil were detected by ion pair extraction derivatization gas chromatography-four grade rod mass spectrometry method in this thesis.At the same time,the corresponding assessments of dioxins levels in dyes were made through the established method of isotope dilution high-resolution gas chromatography/high-resolution mass spectrometry.A brief description was given as follows:1.carboxylic acid butyl ester,derived from the ion pair at high temperature which produced by pair reagents four butyl ammonium hydrogen sulfate(TBAHS)and perfluorinated carboxylic acid(PFCAs),was analysed qualitatively by gas chromatography-mass spectrometry(GC-MS)in our experiment.The conditions of ion pair extraction and derivativation were optimized.It is concluded that,under the full scan and EI+ source conditions,[C4H9]+m/z=57,[CF3]+m/z=69,[C2F4]+m/z=100,[C2F5]+m/z =119,[C3F5]+m/z=131,[C3F7]+m/z=169,and[C4F7]+m/z=181 were the common ions of perfluorinated carboxylic acid butyl ester,which can be used as the qualitative evidence.2.According to the qualitative results of perfluorinated carboxylic acid butyl ester in second chapter,the contents of six kinds of perfluorinated carboxylic acid in soil were determined by ion pair extraction and gas chromatography-mass spectrometry(GC-MS)spectro-metry.The common ions of perfluorinated carboxylic acid butyl ester were selected as monitoring ions and were subsequently used to analyse quantitatively with selected ion monitoring(SIR)mode based on the different peak time.The extraction method of target analyte and the purification conditions of the LC-18 column were optimized.The results displayed that the linear relationship between the concentrations of six kinds of perfluorinated carboxylic acid and their corresponding butyl ester peak area is r>0.996,that the quantitative detection limit(S/N=10)were found to be 12.2,9.31,3.01,0.33,0.23 and 0.24ng/mL for PFC6A?PFC11A respectively,and that RSD values varied from 1.87%to 4.82%(n=7).Under the best accelerated solvent extraction(ASE)extrac-tion conditions,the recovery efficiency of standard addition was more than 82.3%in soil,and the contents of perfluorinated carboxylic acid in soil samples which were collected from Taizhou were determined.3.Seventeen kinds of 2,3,7,8-Chlorine substi-tuted dioxins(PCDD/Fs)in dye were determined with the method of isotope dilution high-resolution gas chromatography/high resolution mass spectrometry(HRGC-HRMS)which was developed from the multistage mixing silica gel column purification and activated carbon column separation of the target by using Soxhlet extraction.And the dioxins in actual dye sample were also detected.It was found that the content of dioxins were low in samples,the detection limit of the method reached to be 0.1pg/g,and the recovery efficiency the purefied interior label marked by isotope was between 77.8%-91.8%.