Effect of atmosphere change paths on the induced chemical expansion

Olivier Valentin (1) , Eric Blond (1) , Aurélie Julian (2) , Nicolas Richet (3)

1 F2ME
2 SPCTS - Science des Procédés Céramiques et de Traitements de Surface
3 CRCD - Centre de Recherche Claude Delorme [Jouy-en-Josas]

This study presents the relevant aspects of the approach developed at Institut PRISME to model strain in the mixed ionic and electronic conductors (MIEC) membrane for reforming of methane into synthesis gas (H2/CO). This macroscopic approach is based on the assumption of strain partition and on the choice of oxygen activity as a state variable. It leads to a thermo-chemo-mechanical model taking into account oxygen diffusion as well as elastic, thermal and chemical expansion phenomena. A chemical expansion model is proposed. The kinetics of a macroscopic bulk diffusion model has been fitted by simulation to chemical dilatometry tests. The transient and the steady-state stress distribution in a membrane reactor for partial oxidation of methane (POM) have been simulated in various conditions.

Mots clés: Mixed conductors; Membrane; Chemical expansion model; Oxygen vacancy

Domaines: Mécanique des matériaux [physics.class-ph]; Mécanique des matériaux [physics.class-ph]

Olivier Valentin, Eric Blond, Aurélie Julian, Nicolas Richet. Effect of atmosphere change paths on the induced chemical expansion. Ceramics materials, 2010, 62 (3), pp.283-287. ⟨hal-00604468⟩