Influence of glass and gold sealants materials on oxygen permeation performances in La0.8Sr0.2Fe0.7Ga0.3O3−δ perovskite membranes

Gas dissociation with a ceramic membrane is an economical and environmental attractive process for methane gas conversion into syngas (mixture of H2 and CO). For this application, the membrane materials require mixed ionic and electronic conductivities in a large range of pO2 resulting in an excellent oxygen semi-permeation of the membrane to improve methane conversion. In this paper, particular attention is given to the influence of sealant materials on oxygen semi-permeation performances of membrane materials. For instance, oxygen semi-permeation measurements have been performed with La0.8Sr0.2Fe0.7Ga0.3O3−δ membranes under an oxygen partial pressure gradient at temperatures from 700 °C to 1000 °C with different sealing materials (glass or gold ring sealant) between the membrane and the support. The result leads to a better understanding of the effects of sealing on oxygen transport through the La0.8Sr0.2Fe0.7Ga0.3O3−δ membrane. Indeed, a gold sealing material is required for accurate measurements of oxygen semi-permeation flux.

Research highlights▶ The oxygen semi-permeation measurements depend on sealant materials. ▶ The oxygen flux through the membrane is governed by oxygen surface exchanges kinetics. ▶ The chemical contamination of the membrane surfaces affects the oxygen flux. ▶ Gold sealant is the best material for membrane sealing. ▶ The use of glass sealant in a cold zone of the reactor is required for industrial use.