Journal of Materials Science

, Volume 17, Issue 9, pp 2649–2656 | Cite as

Diffusion studies of porous materials

Part 2 Effects of thermal and radiolytic oxidation on the pore structure of a “high-reactivity” nuclear graphite
  • J. D. Clark
  • P. J. Robinson
Article

Abstract

Measurements of transient diffusion phenomena are reported for a “high-reactivity”, 20% open-pore volume (OPV), nuclear graphite, in the virgin state and after thermal oxidation in air or radiolytic oxidation in a carbon dioxide/carbon monoxide/methane coolant mixture. The volume of restricted access pores (RAPs) in this graphite is small (< 5% of the OPV) and the changes in pore structure with oxidation are in general very similar for thermal and radiolytic oxidation. A significant difference is that the RAP volume decreased (as expected) on slow thermal oxidation, but showed a slight increase during radiolytic oxidation. This is consistent with a model in which the methane is severely depleted in RAPs, which are therefore subject to an effectively uninhibited corrosion.

Keywords

Oxidation Polymer Methane Graphite Pore Structure 

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Copyright information

© Chapman and Hall Ltd 1982

Authors and Affiliations

  • J. D. Clark
    • 1
  • P. J. Robinson
    • 1
  1. 1.Department of ChemistryManchester PolytechnicManchesterUK

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