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Laser-Heated Microfurnace: Gas Analysis and Graphite Morphology

Published online by Cambridge University Press:  18 July 2016

A M Smith*
Affiliation:
Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW 2234, Australia
Bin Yang
Affiliation:
Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW 2234, Australia
Quan Hua
Affiliation:
Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW 2234, Australia
Michael Mann
Affiliation:
Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW 2234, Australia
*
Corresponding author. Email: [email protected]
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Abstract

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We describe progress in developing a novel miniaturized laser-heated “microfurnace” aimed at preparing ultra-small (∼5 μg) graphite samples from CO2 (Smith et al. 2006, 2007, 2010). Recent effort has focused on automation of the process using a LabVIEW interface, which has permitted feedback control of the catalyst temperature as the reaction proceeds and the logging of reaction parameters. We trialed a number of different pure iron catalysts as well as Fe2O3 (which is reduced in situ to iron) and discuss the reaction rates. We studied the graphite morphology by scanning electron microscopy (SEM) and found there is a marked difference in graphite morphology with catalyst type. We assessed how each catalyst performs in the cesium sputter ion source of the ANTARES Accelerator Mass Spectrometry (AMS) facility. We utilized a quadrupole mass spectrometer to study the gas composition during the reaction, in order to better understand the underlying chemical reactions for such small samples and to better estimate the overall efficiency of the process. Results show that all CO2 is converted to CO by reduction on the iron catalyst within a few minutes of applying laser power. The reaction pressure stabilizes after 40 min; however, some CO is not converted to graphite. The cold trap temperature of –80 ° is effective at trapping H2O, so there is little CH4 production.

Type
Methods, Applications, and Developments
Copyright
Copyright © 2010 by the Arizona Board of Regents on behalf of the University of Arizona 

References

Fink, D, Hotchkis, M, Hua, Q, Jacobsen, G, Smith, AM, Zoppi, U, Child, D, Mifsud, C, van der Gaast, H, Williams, A, Williams, M. 2004. The ANTARES AMS Facility at ANSTO. Nuclear Instruments and Methods in Physics Research B 223–224:109–15.Google Scholar
Hua, Q, Zoppi, U, Williams, AA, Smith, AM. 2004. Smallmass AMS radiocarbon analysis at ANTARES. Nuclear Instruments and Methods in Physics Research B 223–224:284–92.Google Scholar
McNichol, AP, Gagnon, AR, Jones, GA, Osborne, EA. 1992. Illumination of a “black box”: analysis of gas composition during graphite target preparation. Radiocarbon 34(3):321–9.Google Scholar
Santos, GM, Mazon, M, Southon, JR, Rifai, S, Moore, R. 2007a. Evaluation of iron and cobalt powders as catalysts for 14C-AMS target preparation. Nuclear Instruments and Methods in Physics Research B 259(1):308–15.CrossRefGoogle Scholar
Santos, GM, Southon, JR, Griffin, S, Beaupre, SR, Druffel, ERM. 2007b. Ultra small-mass AMS 14C sample preparation and analyses at KCCAMS/UCI Facility. Nuclear Instruments and Methods in Physics Research B 259(1):293302.Google Scholar
Smith, AM, Hua, Q, Williams, AA, Thorpe, KJ. 2006. A novel laser-heated micro-furnace for the preparation of microgram-sized AMS graphite targets. Abstract 55. 19th International Radiocarbon Conference, 3–7 April 2006, Oxford, UK.Google Scholar
Smith, AM, Hua, Q, Levchenko, VA. 2007. New developments in micro-sample 14C AMS at ANSTO. INQUA 2007 Abstracts. Quaternary International 167–168:390.Google Scholar
Smith, AM, Hua, Q, Williams, A, Levchenko, V, Yang, B. 2010. Developments in micro-sample 14C AMS at the ANTARES AMS facility. Nuclear Instruments and Methods in Physics Research B 268(7–8):919–23.Google Scholar
Xu, S, Dougans, A, Freeman, SPHT, Maden, C, Loger, R. 2007. A gas ion source for radiocarbon measurement at SUERC. Nuclear Instruments and Methods in Physics Research B 259(1):7682 CrossRefGoogle Scholar