Study On The Detection Of POPs In Water By Combining Membrane Separation-enrichment-instrument Analysis Technique

In recent years, the rapid development of membrane separation technology, membraneseparation technology has been widely used in water quality measurement-Ultrafiltrationmembrane filter sampl. Therefore the development of membrane separation technology in theseparation and enrichment method based on sample, will likely get a new POPs of separation andenrichment method. The hollow fiber membrane extraction, ionic liquid membrane extraction,membrane separation technology for pretreatment based on of POPs in water enrichment andseparation method, and through the existing analysis instrument and equipment, the developmentof water ultra trace POPs separation enrichment monitoring one of the new technology.Firstly, the selection of PP hollow fiber membrane, made of hollow fiber membranesupported liquid membrane extractor, the hollow fiber membrane extraction–gas phasechromatography method was used to detect the organic chlorine pesticide in water environment,investigate its feasibility. The results showed, eight organo-chlorine pesticides have good linearranges between0.5μg/L and10μg/L. Enrichment times and recovery rate of eight organo-chlorinepesticides reached389-464,77-92%, respectively. This method can meet the demand of analysisof real water sample.Secondly, the determination method for organo-chlorine pesticide in water using hollow fibermembrane liquid microextraction couple with gas phase chromatography was developed. Theeffects of extracting system, extraction time, pH value, mixing speed and extraction temperatureon recovery of organo-chlorine pesticide in water were investigated and the optimum extractionconditions were gained and listed as follow: with n-hexane/toluene as organic extractant,extraction time20min, extraction temperature40℃, mixing speed500rpm, neutral solution.Under the optimum conditions, the recovery of α-666、β-666、γ-666、δ-666、P,p’-DDE、P,p’-DDD、o,p’-DDT、P,p’-DDT in actual sample were103.8%、57.1%、73.1%、61.3%、88.4%、78.8%、111.5%、68%, respectively. This method can meet the demand of analysis ofreal water sample.Then, supported ionic liquid membrane was prepared by fixing1-hexyl-3-methylimidazoliumhexafluorophosphate in the non-woven. The organo-chlorine pesticide were separated andenriched bu liquid phase microextraction. The concentration of organo-chlorine pesticide in waterwas determined using gas phase chromatography. The extraction conditions: extraction time, initial concentration of organo-chlorine pesticide, extraction system, pH value, stripping time andstripping agent volume were optimized. Under the optimum conditions, the recovery of eightorgano-chlorine pesticide in actual sample was77.5%-86.2%. The results showed that this methodis feasible for determination of organo-chlorine pesticide in water.Finally, using a new method--hollow fiber pervaporation and gas chromatography in thedetermination of α-666、β-666、γ-666、δ-666、P,p’-DDE、P,p’-DDD、o,p’-DDT、P,p’-DDTeight organo-chlorine pesticide. The PDMS/PES hollow fiber composite membrane prepared by aspin coating method, and the production of hollow fiber pervaporation membrane component,enrichment effects on pervaporation membrane separation and enrichment method oforganochlorine pesticides in water. The results show that, the separation of hollow fiberpervaporation and gas chromatography method can make8kinds of pesticide mixture can getbetter, and improve the POPs separation and enrichment ratio, reduce the extraction solventvolume, recovery rate is higher than87.5%, it has important significance to trace persistentsurveillance and detection of a machine pollutants.