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Evaluation of Pyro Cube for Deuterium of Hair. By Paul Middlestead and Michelle Chartrand Ottawa University , G.G. Hatch Lab At the request of Paul Brooks, thanks big guy Calgary, Asita 2013, 19 th edition and still going…. What is a Pyrocube ?. From elementar : v ario PYRO cube.
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Evaluation of Pyro Cube for Deuterium of Hair By Paul Middlestead and Michelle Chartrand Ottawa University , G.G. Hatch Lab At the request of Paul Brooks, thanks big guy Calgary, Asita 2013, 19th edition and still going…
Note: No endorsementfromthisguy. All manufacturersmakeproductsthat (usually) deliver. In this case, the PYRO is an alternative to the TC/EA in our lab. Bothsystems are fine and wellsupported. The PYRO isnewer on the market and thisis a preliminaryevaluation
Ceramic and Glassycarbon tubes : 30mm and 18mm • Glassycarbon chips packing + soot • Bottom feeder • Purge and trapseparation • Crucible: 2,0 cm3+ (400 samples) • TCD + software + computer • 120/80 samplesheatedcaroussel (open, large holes) • 125ml/min flow • Furnace on steroids + brain • Can beupgraded to CNS • Sleep mode • Ceramic and Glassycarbon tubes : 18mm and 12mm • Glassycarbon chips packing • Bottom feeder • GC columnseparation 5A • Crucible: 0,75 cm3 (200 samples) • No TCD, no software, no computer • 30/50/100 samplescaroussel (close, smallholes) • 80ml/min flow • Furnace on steroids
IRMS IRMS
100 ml/min IRMS 25 ml/min TCD • Bottom feeder independant flush, 130ml/min • More spacebetweenglassycarbon and ceramic • Fresh He for CO desorption on chemicaltrap • Bypass for Hydrogen mode • TCD for % of H2 and Oxygen • Carrier flow of 125ml/min 2-3 mm He
Different modes, differentpackings • O mode: CO column in line, H isignored • H-O mode: CO column in line • H mode: No CO column in line
H mode reactor No CO column Crucible Wefound H-mode packing to workwell in all modes Glassycarbon chips Ag wool Qtzwool Bottomconnector
H-O mode reactor CO column Crucible Graphite felt Carbon black Glassycarbon chips Spacer Qtzwool Bottomconnector
O mode reactor CO column Crucible Graphite felt Carbon black Glassycarbon chips Spacer Qtzwool Bottomconnector
Biggerisbetter ? • Larger tubes = more surface = lessrepacking • Largercrucible = more area = lesscruciblication • Larger tubes = more surface = smallerpeaks • Larger tubes = more $$$$ but last longer…
Wake up! • Have younoticed the major differencewith the PYRO in H mode? • Somethingunthinkable • Something not usuallyseen or used • Somethingunnatural for analyticalreason • Hint: no divorce
IRMS Bypass of CO column… No separationbetween CO and H2
Typical TC/EA run Flow: 95ml/min GC temp: 90C Peakwidth: 80s Peakheight: 10,6V Peak area: 93,5
TypicalPyrorun O-H mode Flow: 125ml/min Peakwidth: 78s (80) Peakheight: 4,6V (10,6) Peak area: 51,5 (93.5) WHY SMALLER? LARGER VOLUME + FASTER CARRIER FLOW (i.e.dilution) ADDITION OF SOOT: MAGICAL….withoutfractionation
TypicalPyrorun H mode Flow: 125ml/min Peakwidth: 88s (80) Peakheight: 7,0V (10,6) Peak area: 76 (93.5) No CO column! No soot
TypicalPyrorun H mode, TCD USELESS OMG, this is so cool !
For fun, O-mode only, TCD IGNORED !
Pyro linearity Hair, 0,051 to 1,000 mg
For Deuterium , what standards? First: It is imperative to normalise using a decent spread of values for Deuterium analysis, best to bracket the samples with standards of similar matrix.
For Deuterium , what standards? • Polyethylene foil IAEA-CH-7 -100.3 YES • Oil NBS-22 -117 (?) • Biotite NBS-30 -66 (?) • Some hair now available from USGS: • USGS 42: -78,5 USGS 43: -50,3 • Water stds in Silver capillaries (thanks Ty) • Sweet nothing KAOLINITE Kga-1: -58
Methodology for hair (or exchangeable material) 16 -212 AUTOSAMPLER
First, check the standards! NO EXCHANGE !!!!!
This PYRO curve is exactly as all others curves done on TC/EA
Just for fun NBS-30 Biotite test: -61,4 -63 (-66) Not bad, this is a tough cookie! Lets not split hairs!
Real hair test Samples back-exchanged with air in auto sampler
Conclusion • Pyro peak, in H mode, is about 80% of TC/EA • Run time of Pyro is about 50% shorter (H-mode) • Same calibration equations • Pyro appears to be less linear, but better in low range • Very comparable instruments • Higher output: faster running, less down time • No zero blank auto sampler: back exchange of H
We would like to thank: Paul Brooks, Wendy Abdy, Patricia Wickham, Gilles St-Jean, Scott Hughes, Robin Sutka and the Gods of Pyrolisis.