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Pah's Polynuclear Aromatic Hydrocarbon's APPLICATION NOTE PAH’S POLYNUCLEAR AROMATIC HYDROCARBON’S Capillary gas chromatography with flame ionisation detection (FID) or mass spectrometry are the techniques most frequently used for analysing the 16 PAH's targeted by the US EPA. Although there are only 16 compounds in this separation, many problems are encountered with this analysis. These include inadequate resolution of isomers, very long analysis times and excessive levels of column bleed which interfere with peak identification and quantitiation. SGE offer the BPX5, BPX35 and HT8 range of columns which overcome all of these problems. Column Part No.: 054675 Phase: HT8, 0.25 μm Column: 25 m x 0.22 mm ID Initial Temp.: 150 °C, 1 min Rate: 15 °C/min Final Temp.: 380 °C, 5 min Carrier Gas: Helium, 20 psi Detector: FID, 400 °C *Peak identifications are shown in Table 1. Figure 1. Rapid Analysis using an HT8 Column RAPID SCREEN ANALYSIS For rapid analysis of PAH’s not requiring the separation of the benzo (b) and (k) fluoranthene isomers the Column Part No.: 054675 HT8 range of columns are the best choice. Figure 1 Phase: HT8, 0,25 μm Column: 25 mm x 0.22 mm ID shows the separation of all 16 EPA nominated PAH's Initial Temp: 80 °C (with the exception of the two benzofluoranthene Rate: 20 °C/min Final Temp: 380 °C, 1 min isomers) in only 18 minutes. This short analysis results Detector: Ion Trap MS from the ability of HT8 columns to operate routinely Injection Mode: PTV at very high temperatures. Column bleed levels are CarrierGas: He, 15 psi also extremely low. This is well illustrated in Figure 1. Benzo (b,j,k) fluoranthene 1 where effectively no baseline change is observed 2. Benzo (a) fluoranthene 3. Benzo (e) pyrene even when the final temperature is 380 °C. 4. Benzo (a) pyrene 5. Perylene Although separation of all benzofluoranthene isomers cannot be achieved by the HT8 column certain other PAH isomer separations can be performed which are difficult to achieve using conventional polysiloxane phases. Illustrated in Figure 2 the separation of ben- zo (e) pyrene and perylene from benzo (a) pyrene is easily achieved with the HT8 column even with a temperature program rate of 20 °C/min (Figure 2). Figure 2. Selectivity of the HT8 Column www.sge.com APPLICATION NOTE APPLICATION NOTE RESOLUTIONAPPLICATION OF ALL NOTE16 EPA PAH’S RESOLUTIONThe BPX5 and BPX35 OF ALL range 16 of EPA columns PAH’S (5% and Column Part No.: 054142 Phase: BPX5, 0.25 μm 35%RESOLUTION phenylpolysilphenylene-siloxane OF ALL 16 EPA PAH’S respec - Column: 30 m x 0.22 mm ID The BPX5 and BPX35 range of columns (5% and ColumnInitial Temp: Part No.: 054142100 °C, 1 min tively) provide excellent separation of the prob- Phase: BPX5, 0.25 μm 35% phenylpolysilphenylene-siloxane respec- Rate: 5 °C/min lemThe PAH'sBPX5 andpairs: BPX35 range of columns (5% and Column:FinalColumn Temp: Part No.: 30300054142 m °C, x 0.22 20 min mm ID tively) provide excellent separation of the prob- InitialCarrierPhase: Temp: Gas: 100Helium,BPX5, °C, 0.25 120 min psiμm 35% phenylpolysilphenylene-siloxane respec- Rate: 5 °C/min lem PAH's pairs: Detector:Column: FID,30 m 370°C x 0.22 mm ID •tively) phenanthrene/anthracene provide excellent separation of the prob- FinalInitial Temp: Temp: 300100 °C,°C, 201 min min CarrierRate: Gas: Helium,5 °C/min 20 psi •lem chrysene/benzo PAH's pairs: (a) anthracene *Peak identifications are shown in Table 1. • phenanthrene/anthracene Detector:Final Temp: FID,300 370°C°C, 20 min • indeno (1,2,3-cd) pyrene/dibenzo (a,h) Carrier Gas: Helium, 20 psi • chrysene/benzo (a) anthracene *Peak identifications are shown in Table 1. • anthracenephenanthrene/anthracene Detector: FID, 370°C • indenobenzo (b) (1,2,3-cd) and (k) fluoranthenepyrene/dibenzo (a,h) • chrysene/benzo (a) anthracene *Peak identifications are shown in Table 1. anthracene • indeno (1,2,3-cd) pyrene/dibenzo (a,h) • benzo (b) and (k) fluoranthene BPX5 anthracene and BPX35 columns also have column bleed levels• benzo similar (b) and to the (k) HT8fluoranthene range of columns. These BPX5low levels and BPX35ensure columns that positive also have identification column bleed and levels similar to the HT8 range of columns. These accurateBPX5 and quantitation BPX35 columns of alsothe latehave eluting column PAH's bleed low levels ensure that positive identification and (abovelevels similar 300 °C). to the HT8 range of columns. These accurate quantitation of the late eluting PAH's low levels ensure that positive identification and (above 300 °C). Figureaccurate 4 isquantitation a chromatogram of the of late the eluting16 EPA PAH'sPAH's obtained(above 300 using °C). the medium polarity BPX35 Figure 3. PAH’s analysis using a BPX5 column Figurecolumn. 4 Medium is a chromatogram polarity columns of the like 16 theEPA BPX35 PAH's obtained using the medium polarity BPX35 Figure 3. PAH’s analysis using a BPX5 column haveFigure always 4 is a beenchromatogram popular for of PAH the 16applications. EPA PAH's column. Medium polarity columns like the BPX35 However,obtained dueusing to thethe restricted medium upper polarity temperature BPX35 Figure 3. PAH’s analysis using a BPX5 columnColumn Part No.: 054714 havelimits alwaysand high been column popular bleed for PAH levels applications. non-polar Phase: BPX35, 0.25 μm column. Medium polarity columns like the BPX35 Column: 30 m x 0.22 mm ID However,columns like due the to theBPX5 restricted are more upper commonly temperature used. ColumnInitial Temp: Part No.: 054714100 °C have always been popular for PAH applications. Phase: BPX35, 0.25 μm limitsThis is andnot thehigh case column for the bleed BPX35 levels column. non-polar With a Rate: 10 °C/min However, due to the restricted upper temperature Column:FinalColumn Temp: Part No.: 30360054714 m °C, x 0.22 10 min mm ID columns like the BPX5 are more commonly used. Initial Temp: 100 °C maximumlimits and operatinghigh column temperature bleed levels of 370 non-polar °C and CarrierPhase: Gas: He,BPX35, 25 psi 0.25 μm Thiscolumn is not bleed the case specifications for the BPX35 similar column. to a With BPX5 a Rate:Detector:Column: 10FID,30 °C/minm 380 x 0.22 °C mm ID columns like the BPX5 are more commonly used. FinalInitial Temp: Temp: 360100 °C,°C 10 min maximum operating temperature of 370 °C and columnThis is not these the problemcase for thehave BPX35 been column. eliminated. With As a CarrierRate: *Peak Gas: identifications He,10 are °C/min25 shown psi in Table 1. column bleed specifications similar to a BPX5 Detector:Final Temp: FID,360 380°C, 10°C min amaximum result higher operating operating temperature temperatures of 370 can°C andbe column these problem have been eliminated. As Carrier Gas: He, 25 psi usedcolumn reducing bleed thespecifications analysis time similar for the to 16 a PAH'sBPX5 Detector:*Peak identificationsFID, are 380 shown °C in Table 1. a result higher operating temperatures can be tocolumn approximately these problem 30 minutes. have been eliminated. As used reducing the analysis time for the 16 PAH's *Peak identifications are shown in Table 1. a result higher operating temperatures can be to approximately 30 minutes. used reducing the analysis time for the 16 PAH's to approximately 30 minutes. Figure 4. PAH’s analysis using a BPX35 column Figure 4. PAH’s analysis using a BPX35 column Table 1 Figure 4. PAH’s analysis using a BPX35 column Table16 1 EPA PAH Compounds 6. Anthracene 12. Benzo (k) fluoranthene 1. Naphthalene 7. Pyrene 13. Benzo (a) pyrene Table 1 162. AcenaphthyleneEPA PAH Compounds 6.8. AnthraceneFluoranthene 12.14. BenzoIndeno (k) (1,2,3-cd) fluoranthene pyrene 1. Naphthalene 7. Pyrene 13. Benzo (a) pyrene 3.16 Acenaphthene EPA PAH Compounds 9.6. ChryseneAnthracene 15.12. DibenzoBenzo (k) (a,h) fluoranthene anthracene 2. Acenaphthylene 8. Fluoranthene 14. Indeno (1,2,3-cd) pyrene 4.1. FluoreneNaphthalene 10.7. Pyrene Benzo (a) anthracene 16.13. BenzoBenzo (g,h,i)(a) pyrene perylene 3. Acenaphthene 9. Chrysene 15. Dibenzo (a,h) anthracene 5.2. PhenanthreneAcenaphthylene 11.8. Fluoranthene Benzo (b) fluoranthene 14. Indeno (1,2,3-cd) pyrene AP-0044-D © SGE Analytical Science Pty Ltd October 2008 4. Fluorene 10. Benzo (a) anthracene 16. Benzo (g,h,i) perylene 3. Acenaphthene 9. Chrysene 15. Dibenzo (a,h) anthracene 5. Phenanthrene 11. Benzo (b) fluoranthene SGE4. GCFluorene columns are all available from10. Kinesis Benzo (a) anthracene 16. Benzo (g,h,i) perylene AP-0044-D © SGE Analytical Science Pty Ltd October 2008 Kinesis5. Phenanthrene Ltd Kinesis GmbH (formerly11. Benzo Abimed) (b) fluorantheneKinesis Inc Kinesis Australia Pty Ltd www.sge.comTel: +44 (0)1480 212122 Tel: +49 (0)2173 89 05-0 Toll free in USA: (866) 934-6353 Tel: +61 (0)7 3829 3996 AP-0044-D © SGE Analytical Science Pty Ltd October 2008 Fax: +44 (0)1480 212111 Fax: +49 (0)2173 89 05-77 Fax: (518) 289 5818 Fax: +61 (0)7 3829 3997 E-mail: [email protected] Email: [email protected] Email: [email protected] Email: [email protected] www.sge.comWeb: kinesis.co.uk Web: kinesisgmbh.de Web: kinesis-usa.com Web: kinesis-australia.com.au www.sge.com.
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