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Modelling of natural graphite oxidation using thermal analysis techniques

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Abstract

A natural graphite recommended for use in nuclear applications was analyzed using thermogravimetric analysis. The oxidation behaviour was unlike that expected for flake-like particles. The dynamic data displayed an apparent bimodal reaction rate curve as a function of temperature and degree of conversion. Nevertheless, it was possible to model this behaviour with a single rate constant, i.e. without the need for a parallel reaction type of kinetic mechanism. The approach used in this paper to model the gas–solid reaction of graphite and oxygen, provides a consistent framework to test the validity of complementary isothermal and non-isothermal data for a specific solid state reaction.

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Abbreviations

E A :

Activation energy (J/mol)

k o :

Arrhenius pre-exponential (1/s)

R :

Gas constant (J/mol K)

\( {\rm P}_{{O_{2} }} \) :

Partial pressure of oxygen (kPa)

t:

Time (s)

T:

Temperature (K)

Y :

Mole fraction (−)

α:

Dimensionless conversion (–)

β:

Temperature scan rate (K/s)

0:

Initial

m, n:

Indices

r :

Reaction order in O2

References

  1. Galwey AK. What can we learn about the mechanisms of thermal decompositions of solids from kinetic measurements?. J Therm Anal Calorim. 2008;92:967–83.

    Article  CAS  Google Scholar 

  2. Galwey AK. Perennial problems and promising prospects in the kinetic analysis of nonisothermal rate data. Thermochim Acta. 2003;407:93–103.

    Article  CAS  Google Scholar 

  3. Galwey AK. Thermochim Acta. Is the science of thermal analysis kinetics based on solid foundations? A literature appraisal. 2004;413:139–83.

    Article  CAS  Google Scholar 

  4. Šesták J, Berggren G. Study of the kinetics of the mechanism of solid-state reactions at increasing temperatures. Thermochim Acta. 1971;3:1–12.

    Article  Google Scholar 

  5. Koga N. Physico-Geometric kinetics of solid-state reactions by thermal analyses. J Therm Anal. 1997;49:45–56.

    Article  CAS  Google Scholar 

  6. Anderson HL, Kemmler A, Höhne GWH, Heldt K, Strey R. Round robin test on the kinetic evaluation of a complex solid state reaction from 13 European laboratories. Part 1. Kinetic TG-analysis. Thermochim Acta. 1999;332:33–53.

    Article  CAS  Google Scholar 

  7. Koga N, Tanaka H. A physico-geometric approach to the kinetics of solid-state reactions as exemplified by the thermal dehydration and decomposition of inorganic solids. Thermochim Acta. 2002;388:41–61.

    Article  CAS  Google Scholar 

  8. Vyazovkin S. Kinetic concepts of thermally simulated reactions in solids: a view from a historical perspective. Int Rev Phys Chem. 2000;19:45–60.

    Article  CAS  Google Scholar 

  9. Galwey AK, Brown ME. Application of the Arrhenius equation to solid state kinetics: can this be justified?. Thermochim Acta. 2002;386:91–8.

    Article  CAS  Google Scholar 

  10. Gimzewski E. The relationship between oxidation induction temperatures and times for petroleum products. Thermochim Acta. 1992;198:133–40.

    Article  CAS  Google Scholar 

  11. Zaghib K, Song X, Kinoshita K. Thermal analysis of the oxidation of natural graphite: isothermal kinetic studies. Thermochim Acta. 2001;371:57–64.

    Article  CAS  Google Scholar 

  12. Galwey AK. What theoretical and/or chemical significance is to be attached to the magnitude of an activation energy determined for a solid-state composition? J Therm Anal Calorim. 2006;86:267–86.

    Article  CAS  Google Scholar 

  13. Galwey AK. Eradicating erroneous Arrhenius arithmetic. Thermochim Acta. 2003;399:1–29.

    Article  CAS  Google Scholar 

  14. Hurt RH, Haynes BS. On the origin of power-law kinetics in carbon oxidation. Proc Combust Inst. 2005;30:2161–8.

    Google Scholar 

  15. Moormann R, Hinssen H-K. Basic studies in the field of high-temperature engineering. Presented at second information exchange meeting, Paris, France, 2001, p. 243–54.

  16. Hennig GR. Catalytic oxidation of graphite. J Inorg Nucl Chem. 1962;24:1129–37.

    Article  CAS  Google Scholar 

  17. McKee DW. The catalyzed gasification reactions of carbon. Chem Phys Carbon. 1981;16:183–99.

    Google Scholar 

  18. McKee DW, Chatterji D. The catalytic behaviour of alkali metal carbonates and oxides in graphite oxidation reactions. Carbon. 1975;13:381–90.

    Article  CAS  Google Scholar 

  19. Ranish JM, Walker PL Jr. Models for roughening of graphite during its catalyzed gasification. Carbon. 1990;28:887–96.

    Article  CAS  Google Scholar 

Download references

Acknowledgements

This work is based upon research supported by PBMR and the South African Research Chairs Initiative of the Department of Science and Technology and the National Research Foundation. Any opinion, findings and conclusions or recommendations expressed in this material are those of the authors and therefore the PBMR, NRF ad DST do not accept any liability with regard thereto.

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Authors and Affiliations

  1. SARChI Chair in Carbon Materials and Technology, Department of Chemical Engineering, University of Pretoria, Pretoria, 0002, South Africa

    Heinrich Badenhorst, Brian Rand & Walter W. Focke

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  1. Heinrich Badenhorst
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  2. Brian Rand
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  3. Walter W. Focke
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Correspondence to Walter W. Focke.

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Appendix 1

Appendix 1

See Appendix Table 3

Table 3 Conversion function look-up table
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Badenhorst, H., Rand, B. & Focke, W.W. Modelling of natural graphite oxidation using thermal analysis techniques. J Therm Anal Calorim 99, 211–228 (2010). https://doi.org/10.1007/s10973-009-0095-3

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  • DOI: https://doi.org/10.1007/s10973-009-0095-3

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