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Fast and Complete CO2-to-Graphite Conversion for 14C Accelerator Mass Spectrometry

Published online by Cambridge University Press:  18 July 2016

Gert Hut
Affiliation:
Isotope Physics Laboratory, University Groningen, The Netherlands.
H Göte Östlund
Affiliation:
Tritium Laboratory, University of Miami, Florida
Klaas van der Borg
Affiliation:
Fysisch Laboratorium, Rijksuniversiteit Utrecht, The Netherlands
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Abstract

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With Fe powder as a catalyst, CO2 is completely converted to graphite within 90 minutes. The reaction proceeds at 650°C with an excess of H2. The reaction rate is enlarged by forced circulation and by keeping the water vapor pressure very low. The graphite samples obtained, consisting of 5mg of carbon, almost immediately produce stable 12C currents of the order of 20–30μA in the sputter source of a Van de Graaff accelerator. The currents can be maintained for at least 10 hours and are comparable to those from commercial graphite. No memory effects in the preparation system have been observed.

Type
I. AMS Techniques
Copyright
Copyright © The American Journal of Science 

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