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Analysis of PPB Level Volatile Chemicals using Static Preconcentration PowerPoint Presentation
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Analysis of PPB Level Volatile Chemicals using Static Preconcentration

Analysis of PPB Level Volatile Chemicals using Static Preconcentration

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Analysis of PPB Level Volatile Chemicals using Static Preconcentration

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  1. Analysis of PPB Level Volatile Chemicals using Static Preconcentration

  2. Introduction to Sampling and Analysis of Volatile Chemicals Comparison with other VOC Methods Air Analysis - Canister Methods Liquids and Solids - Large Volume Static Headspace (LVSH) Technique Other Applications Summary Presentation Overview

  3. GC/MS Detection Limits vs Headspace Sample Volume 1000 100 10 1 0.1 0.01 10-3 10-4 10-5 Loop Preconcentration PPM LOD Vol vs Conc. 0.001 0.01 0.1 1.0 10 100 1000 MINIMUM VOLUME REQUIRED (CC)

  4. Classical VOC Sampling and Analysis • Air • Tedlar Bags • Adsorbent Tubes • Stainless Steel Canisters (EPA TO14, TO15) • Liquids & Solids • Purge and Trap • Static Headspace - Loop Injection

  5. Classical VOC Sampling and Analysis • Air • Tedlar Bags • Adsorbent Tubes • Stainless Steel Canisters (EPA TO14, TO15) • Liquids & Solids • Purge and Trap • Static Headspace - Loop Injection • Large Volume Static Headspace

  6. Air Sampling Media

  7. Volume Determination • Loop or Syringe Injection • Must equilibrate Sample to Atmospheric • Canister must usually be at positive pressures. • For Sample Volumes under 5 cc P • Mass Flow Time Integration • Canister Can be at Positive or Negative Pressure • Must verify leak free conditions before starting • MFC Downstream of trap reduces carryover • On-line Pressure Sensor monitors trap blockage • For Sample Volumes 10cc and larger MFC

  8. Low Concentration Measurements(EPA Methods TO14 / TO15)

  9. Smaller Canisters (MiniCans) for Higher Concentration Samples

  10. Canisters Tubes Chance For Volume Measurement Errors No Yes Traps Checked for Blank and Analyte Recovery Yes No Allow Repeat Analyses Yes No Chance for Post Cleaning Contamination Minor Yes Permits Sample Screening Yes No Allows Mild Trapping/Desorption Conditions Yes No to Maximize Yields Requires Power for Sampling No Yes Requires Conc. To be known Before Sampling No Yes Advantages Of Canisters Over Tubes

  11. Silonite Coated 6L Canisters

  12. 8 Canister Cleaning System

  13. Glass Filtered Grab Sampling

  14. 1320 32-Position Field Sampler and 1L MiniCans Bridging The Gap Between Tubes and Canisters

  15. Six Sites Monitored with Just 2 Analyzers CS6 CS1 Centralized Lab Analyzers CS2 CS5 1 2 CS3 CS4

  16. 9 1L MiniCans in Carrying Cases

  17. Are 1 Liter Canisters Large Enough? Instrument: 7100 Preconcentrator Application Detector Sample Vol. LOD PAMS FID 400cc 0.1 PPB(c) PAMS 5973 MS 400cc 0.05 PPB(v) Air Toxics 5973 MS 400cc 0.05 PPB(v) Air Toxics (SIMS) 5973 MS 400cc 0.005 PPB(v) Limited to Single Analysis - OK for Continuous Monitoring

  18. Clean 21 (or 42) Canisters Simultaneously • 3 Batches a day equals 63 Canisters • Supports 7 sites with single 21 position manifold • Supports 14 sites with two 21 position manifolds

  19. Analyzing 1L MiniCans

  20. Standard Introduction and Analysis

  21. 7032-LVSH / 7100 /5973 Large Volume Static Headspace Analyzer M3 SL I/O SL I/O M2 6 M1 GC MS 7100 7032-LVSH

  22. 7100 Heated Flow Path • Silonite tubing used throughout. • Complete heating of sample flow path. Easily accessed for trap and tubing replacement. • External Heaters outside each cryotrap 7100 Preconcentrator

  23. SiloniteTM Fused Silica Lined Tubing

  24. 7100 Water and CO2 Management Techniques MFC PUMP Loading Internal Standard N2, O2 Helium Carrier Helium To GC Focuser Glass Beads Tenax Sample Internal Standard Calibration Standard Sample Cryogen in

  25. 7100 Water and CO2 Management Techniques MFC PUMP Loading Calibration Standard Helium Carrier N2,O2 Helium To GC Focuser Glass Beads Tenax Sample Internal Standard Calibration Standard Cryogen in

  26. 7100 Water and CO2 Management Techniques MFC PUMP Loading Sample Helium Carrier N2, O2, Ar, CH4 Helium To GC CO2 H2O Focuser VOCs Glass Beads Tenax Sample Internal Standard Calibration Standard Cryogen in

  27. 7100 Water and CO2 Management Techniques MFC PUMP Flushing Traps Helium Carrier N2, O2, Ar, CH4 Helium To GC CO2 H2O Focuser VOCs Glass Beads Tenax Sample Internal Standard Calibration Standard Cryogen in

  28. 7100 Water and CO2 Management Techniques MFC PUMP Removing Water and CO2 CO2 Helium Carrier Helium To GC H2O VOCs Focuser Glass Beads Tenax Sample Internal Standard Calibration Standard Cryogen in

  29. 7100 Water and CO2 Management Techniques MFC PUMP Focusing Sample before Injection Helium Carrier Helium VOCs To GC VOCs Focuser Glass Beads Tenax Sample Internal Standard Calibration Standard Cryogen in

  30. 7100 Water and CO2 Management Techniques MFC PUMP H2O Post-Injection Bakeout Helium Carrier Helium To GC Focuser Glass Beads Tenax Sample Internal Standard Calibration Standard Cryogen in

  31. Fast Injection and Proper Water Management Minimizes Tailing of Polar VOCs Column: HP1, 60m, 0.32mm ID, 1um film. Flow rate: 1.5 ccm Carrier: He

  32. 1 Week TO14 Stability Test 1 Liter MiniCan Concentration: 10 PPB Volume: 400cc Instrument: 7100/5973 GCMS Column: HP1, 60m, 0.32ID, 1um Column Start Temp: 35 deg. C

  33. TO15 Precision Study using 7100 Preconcentrator and 5973 GCMS Data Compliments of: Columbia Analytical Jacksonville, Florida

  34. TO15 Precision Study using 7100 Preconcentrator and 5973 GCMS Data Compliments of: Columbia Analytical Jacksonville, Florida

  35. TO15 Precision Study using 7100 Preconcentrator and 5973 GCMS Data Compliments of: Columbia Analytical Jacksonville, Florida

  36. C2-C10 GC/FID Analysis - Light Ends GC: 5890 Column: 60m, 0.32mmID, 1um, DB1 Preconc: MP&T, 400cc, 30ppbc Std GC Start Temp: -50 for 4 minutes

  37. Vinyl Chloride 100x Calibration Curve usingVariable Volume / Single Standard Calibration

  38. Multiple Preconcentration Options Depending on Target Compounds and Matrix (CO2, ETOH) Better Recovery of Thermally Labile Flavor and Odor Compounds: Strong Carbon Based Adsorbents are Avoided Inert, Silonite Tubing used Throughout Reduced Temperature Trapping Minimizes Sample Stress Advantages of 7100 Multi-Stage Preconcentration

  39. Introduces 10-200cc of headspace to the 7100 Preconcentrator Accommodates solids and liquids Detection limits 100x lower than conventional loop injection headspace “See what you can smell” Large Volume Static Headspace Autosampler

  40. LVSH Sample Platforms and Enclosures • Samples are placed in disposable vials, reducing potential for contamination of sample platforms. • Sample Platforms use quick connects, simplifying removal for oven bakeout.

  41. Cheddar Cheese by LVSH/GCMS Cheddar Cheese, Brand A 100cc, LVSH 60m, HP1, 0.32mm ID, 1um 7032LVSH/7100/5973 Cheddar Cheese, Brand B 100cc, LVSH 60m, HP1, 0.32mm ID, 1um 7032LVSH/7100/5973 Toluene

  42. Beer by LVSH/GCMS Beer, EtOH Removed 200cc, LVSH 60m, HP1, 0.32mm ID, 1um 7032LVSH/7100/5973 EtOH

  43. Advantages of Large Volume Static Headspace (LVSH) over Purge and Trap • Cleaner. No aerosols or foaming to contaminate sample transfer lines • Better Recovery of Thermally Labile Flavor and Odor Compounds: • Strong carbon based adsorbents are avoided • Inert, Silonite tubing used throughout • Reduced temperature trapping minimizes sample stress, improving recovery and reducing artifact formation • Better matrix elimination using 3-stage trapping • More accurate determination of steady state distribution of chemicals in the sample headspace • Allows direct comparison of liquid, solid, and gas phase collected samples

  44. Advantages of Large Volume Static Headspace (LVSH) over SPME • Less discrimination against light end compounds • LVSH is a closed system. Little chance of contamination with room air • Lower detection limits, especially for more volatile compounds • SPME cannot compare liquid, solid, and gas phase collected samples

  45. LVSH Analysis of Yuban Coffee - 100cc

  46. LVSH Analysis of Banana - 100cc

  47. 100cc LVSH Analysis of Dannon Raspberry Yogurt

  48. 100cc LVSH - Coke/Pepsi Challenge Coke Pepsi

  49. Using LVSH to Determine Product Quality Markers in Fruits and Vegetables • Analysis of 100cc of Headspace allows detection of VOCs indicating condition of food products. • Monitoring changes in VOC ratios as food spoils allows quantitative evaluation of extent of spoilage. • Once specific “Markers” are determined, remote headspace techniques can be used to predict food condition and time until spoilage in storage containers and warehouses.