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Elemental, My Dear Watson

Paul Middlestead University of Ottawa, G.G. Hatch Laboratory For 20th Continuous Flow Conference, Davis, 2014. Elemental, My Dear Watson. This talk is for new users We will touch the basics on Elemental analysers A mix bag of tricks and advices

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Elemental, My Dear Watson

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  1. Paul Middlestead University of Ottawa, G.G. Hatch Laboratory For 20th Continuous Flow Conference, Davis, 2014 Elemental, My Dear Watson

  2. This talk is for new users • Wewilltouch the basics on Elementalanalysers • A mix bag of tricks and advices • Refer to manufacturer’s instruction manuals • Onlyendorsedproducts are: RickardsRedand Rickards White ! Who/whatisthis talk for?

  3. EA TC/EA Combustion Pyrolysis NCHS HO Large capacity S only TOC Stable isotopes Meetmyfamily 12000C 15000C

  4. Lecois the mostpopular manufacturer of elementalanalysers. Everydepartment has one or two of thoseaccumulatingdust. • Static combustion usingoxygen: not suitable for IRMS. Meet Grand Pa

  5. Let’s touch on • Elemental Analyser as an…instrument • Schematics • Autosamplers • Flash combustion • Chemicals & Configurations • Gas Chromatography • Thermal Conductivity Detector • Typical run • Common problems • EA-IRMS

  6. Simultaneous determination of Nitrogen, Carbon, Hydrogen, Sulfur, Oxygen • Measuring range: 100 ppm to 100% • Sample size: 0.1 to 1000 mg / 0.1 to 25 ul • Detection limit: 10 ppm • Accuracy: 0.3% - 0.02% absolute EA as an …. instrument

  7. CE instruments (Carlo Erba) models 1108, 1110, NA 1500, NA 2100, Flash 1112, Flash 2000 • Costech Model ECS4010 • Elementar cube family • Eurovector models EuroEa3028-HT, Ea3024-IRMS, pyrolysis model • Sercon-Integra2 • TC\EA Thermo • … Manufacturers, models blablabla

  8. Organic compounds • Pharmaceuticals • Organometallics • Petrochemicals • Gasoline & fuels • Graphite • Carbides & nitrides • Metals & alloys • Polymers • Explosives • Hydrocarbons • Soils • Coal & coke • Liquids EA : Bulk analysis of NCHS/O In short, you can combust your grandmother!

  9. Typical EA setup with IRMS Ref gas 1 He Ref gas 2 2 m Elemental Analyser (CNS) (OH) Isotope Ratio Mass Spectrometer Interface

  10. EA picture

  11. Autosampler He O2 Gas chromatography Column in oven Thermal Conduc- tivity Detector Water Trap EA line out TCD Elemental Analyser Schematic CO2 N2 Reduction Chemicals 650C Combustion Chemicals 1020C H2O SO2

  12. Found the problemwith the previous slide?A beer if you do…(5 seconds)

  13. Autosampler He O2 Gas chromatography Column in oven Thermocouple Detector Water Trap EA line out TCD Elemental Analyser Schematic CO2 N2 Reduction Chemicals 700C Combustion Chemicals 1020C H2O SO2

  14. A cold Rickard’sRedfor me please.

  15. Sample/Std is weighed and wrapped in tin foil, placed in culture tray/autosampler • Sample drops is flash-combusted in O2 in He stream, causing rapid cracking and oxidation of gases stoichiometrically equivalent to their elemental components, some gas oxides need to be reduced before obtaining final products (N2, CO2, H2O, SO2) i.e. oxidation and reducing reactions involved Typical Analysis Procedure for EA

  16. Separation of gases by gas chromatography or chemical column traps • Detection by thermal conductivity detector (TCD) or IRMS. • Curve made from weighing certified stds (for isotope and/or quantitative measurements) Typical Analysis Procedure for EA

  17. Some torture tools…

  18. Wellwell, got culture?

  19. Supersizeme

  20. MAIS C’EST IMPOSSIBLE!

  21. Filters? Careful! C’EST FANTASTIQUE!

  22. Not flat please

  23. Autosamplers (AS200)

  24. Zero Blank

  25. Zero Blank modified

  26. Special tools required ECS 4010

  27. Take 20 minutes to study the gasschematics of your instrument Be good to yourself

  28. Combustion starts Flash should occur within 2-3 seconds of being dropped Injected O2 Sample drops START Sample dropping 10 20 30 40 0 seconds

  29. PLATINUM: Absorbs much of the heat of the reactor before passing it on to the sample, slowing down reaction • ALUMINIUM: Supplies good oxidation flash and prime sample ignition but does not melt or mix with the sample thus does not promote inner oxidation • SILVER: Melts at 9600C, does not take part in the combustion, retains trace of carbon when in molten state • TIN: Inexpensive & takes active part in process. Melts at 2350C with very low enthalpy, intermixes with organic and inorganic substances, expedites the final oxidation reaction Why you Tin man?

  30. C CO2 CO2 Reduction tube Combustion tube N N2 + NxOx N2 HH2O H2O Let’s get cracking S SO2 + SO3 SO2

  31. System should be optimized for element(s) to be analyzed • One-tube system: both oxidant catalyst and reducing chemicals in one tube; usually used if S is to be analyzed • Two-tube system: one tube for oxidant, one tube for reducing chemicals; usually used for N, NC or NCH • Chemical traps: Mg Perchlorate or Anhydrone will trap H2O, and Carbosorb will trap CO2 (and SO2) Chemicals and Configurations

  32. ConfigurationCN

  33. ConfigurationS

  34. Small isbeautiful

  35. Usinggrindingtools and dilutedNitricacid, one canre-use combustion and reduction tubes More torture tools

  36. Gas chromatographic columns will separate different components according to their polarity and molecular size. • Factors influencing the quality of the chromatography: column length, size of packing, tube diameter, stationary phase type, flow rate, temperature. • Packed column: packed polymer beads, different sizes available. High capacity , low resolution. • Capillary column: small capillary with polymeric film on inner wall. High resolution, low capacity. • Deactivated fused silica is free of adsorption problems encountered with most packings or capillaries columns. Gas Chromatography

  37. He + N2 , CO2 , H2O , SO2 + He He + SO2 + H2O+ CO2 + N2 + He INCREASING POLARITY OF GASES Gas Separation/ GC

  38. He + SO2 + H2O+ CO2 + N2 + He DETECTOR CO2 N2 SO2 H20 DETECTOR What after we separate? TIME

  39. TCD SO2 CO2 H2O Gas Separation / Purge & Trap

  40. Thermal conductivity detector (TCD) Heated filament from which heat is removed at a constant rate by He gas stream. Change in heat transfer is caused by presence of analyte molecules with different thermal conductivities than He. Relatively low sensitivity, excellent range and linearity. Non-destructive. Electron capture detector (ECD) Electrons are captured by organic species in ionized carrier; used for trace sulfur determination. Isotope Ratio Mass Spectrometer (IRMS) Detectors

  41. CO2 Typical output of EA, text book N2 H2O SO2

  42. Balance: Get the best A 0.01mg readability translates in an error of 0.25% on a 2 mg sample (on 100% carbon) Balance

  43. IAEA (and NIST) standards Links available on Isogeochem

  44. Best : %N, 15N, %C, 13C Test differentmaterials and pray Makeyourown: Caffeine L-glutamicacid Mixtures such as sucrose + potassium nitrate Mix in solution of natural + enriched/depleted material then dried, powdered, sieved STD: Makingit on yourown…

  45. STD: Not makingit on yourown…

  46. STD: Not making it on your own… Can also contact other university labs to buy or obtain their internal standards. Arndt Schimmelmann Indiana Universityhttp://mypage.iu.edu/~aschimme/hc.htm

  47. 1. K-Factor (Single point calibration with blank substraction) Calculated % = K * (Area unk – Area blk) Weight unk Where K = Weight std * Theor std % Area std - Area blk Calculation Methods

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