Shaping of 3YSZ porous substrates for oxygen separation membranes

Abstract

In recent years, asymmetric membranes based on mixed ionic-electronic conductors (MIEC) have gained importance in practical gas separations. MIEC ceramic materials show high-energy efficiency and high-temperature resistance, which allows direct integration in industrial processes. Thin layers are supported on porous substrates that provide mechanical strength. In the asymmetric membrane manufacture, the control of support porosity and microstructure is crucial. Colloidal processing is an interesting method that allows controlling the final microstructure in both surfaces and bulk, with high reproducibility. Here, the development of asymmetric membranes with a top functional layer made of Ce 0.8 Gd 0.2 O 1.9 /Ni 2 FeO 4 composite is presented and aims to maximize oxygen permeation and membrane robustness. The porous substrate is prepared by slip casting while the functional layers by screen-printing. The effect of pore former volume and particle morphology were studied. The combination of spherical and flake-like PMMA particles enabled to generate open porosity suitable for fast gas transport.

A review on dual-phase oxygen transport membranes: from fundamentals to commercial deployment

“…From the economic point of view, this solution may not be feasible since membrane materials are normally expensive and considerable amounts of powder are needed for production of the supports. Other alternatives that are usually explored are the use of porous substrates consisting of cheaper materials such as YSZ, 238,248,256 Al 2 O 3 , 257,258 MgO 259-262 and metallic alloys. 263 Several attempts to obtain such robust and high performing asymmetric membranes have been reported.…”

Ice-Templating for the Elaboration of Oxygen Permeation Asymmetric Tubular Membrane with Radial Oriented Porosity

“…To begin, an increase in the porosity of the CGO-Co interlayer would increase the amount of air that reaches the MIEC separation layer, enhancing the overall yield of the membrane. This can be achieved by introducing a certain amount of an organic pore former to the CGO-Co slurry that will decompose during the thermal treatment [34]. Secondly, a reduction in the thickness of the interlayer (CGO-Co) or the MIEC layer (LSCF-CGO) would also increase the oxygen permeation flux, as it is described by Wagner's equation, where J O2 is inversely proportional to the thickness of the layer.…”

Tetragonal phase stability maps of ceria-yttria co-doped zirconia: From powders to sintered ceramics

“…Tetragonal zirconia is a widely studied and technologically important material due to its wide range of applications from structural and engineering ceramics to catalytic materials. Superior mechanical properties of tetragonal zirconia have made it an interesting structural ceramic for use in solid oxide fuel and electrolysis cells, membranes, and biomedical applications [1][2][3][4][5][6][7].…”