Thermo-chemical fuel removal from porous materials by oxygen and nitrogen dioxide
2014 (English)In: Physica Scripta, ISSN 0031-8949, E-ISSN 1402-4896, Vol. T159, 014065- p.Article in journal (Refereed) Published
Thermo-chemical removal (TCR), or baking in reactive gases, is a candidate method to control the co-deposit related tritium inventory in fusion devices. TCR can be understood as reaction-diffusion processes in a porous material. O-2-TCR was applied to 150-550 nm thick a-C:D layers with similar textures. A linear relation between the integral TCR rate and the layer thickness, as predicted by the understanding, was observed in the experiment, i.e. the time to remove the hydrogen inventory is independent of its initial amount. TCR with nitrogen dioxide (NO2) at temperatures of 200-350 degrees C was conducted with a set of a-C:D and W-C-H layers. At 350 degrees C NO2 removed similar to 15% porosity a-C:D within 3 min. The O retention in remaining a-C:D was approximate to 10(17) Ocm(-2). An activation energy of approximate to 0.78 eV for reactions of NO2 with D and C was determined. The results were applied for predictions of the TCR effectivity in ITER. The treatment of W-C-H led to O uptake (O/W approximate to 2-3), while W and C contents remained unchanged.
Place, publisher, year, edition, pages
2014. Vol. T159, 014065- p.
tritium, fuel retention, fuel removal, amorphous carbon, thermo-chemical removal, thermo-oxidation, reaction kinetics
IdentifiersURN: urn:nbn:se:kth:diva-145772DOI: 10.1088/0031-8949/2014/T159/014065ISI: 000334847800066ScopusID: 2-s2.0-84902199733OAI: oai:DiVA.org:kth-145772DiVA: diva2:721609
QC 201406042014-06-042014-06-022014-06-04Bibliographically approved