Université de Fribourg

Manufacturing of tubular dead-end membranes by continuous thermoplastic extrusion

Salehi, Mehdi ; Pfaff, Ewald M. ; Kaletsch, Anke ; Graule, Thomas ; Clemens, Frank ; Grobéty, Bernard

In: International Journal of Applied Ceramic Technology, 2015, vol. 12, p. E13–E18

Dense and gastight dead-end tubular Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) membranes were fabricated by thermoplastic extrusion. Optimal feedstocks for the extrusion of dead-end tubular structures were obtained for a feedstock consisting of 89.83 wt% BSCF powder, 5.63 wt% ethylene vinyl acetate (EVA), 3.56 wt% paraffin wax (PW), and 0.98 wt%...

Université de Fribourg

Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) feedstock development and optimization for thermoplastic forming of thin planar and tubular oxygen separation membranes

Salehi, Mehdi ; Clemens, Frank ; Pfaff, Ewald M. ; Junior, Roberto M. ; Bergmann, Carlos P. ; Diethelm, Stefan ; Neururer, Christoph ; Graule, Thomas ; Grobéty, Bernard

In: Journal of Membrane Science, 2013, p. -

This paper presents the processing steps for producing thin planar and tubular oxygen separation membranes by thermoplastic forming of Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) with polystyrene (PS) and stearic acid (SA) as binder. The influence of powder content on the shape stability of thin membranes (tubular and planar structures)...

Université de Fribourg

Kinetic analysis of the polymer burnout in ceramic thermoplastic processing of the YSZ thin electrolyte structures using model free method

Salehi, Mehdi ; Clemens, Frank ; Graule, Thomas ; Grobéty, Bernard

In: Applied Energy, 2012, vol. 95, p. 147-155

Polymeric binder burnout during thermoplastic processing of yttria stabilized zirconia (YSZ) ceramics were analyzed using thermogravimetric analysis (TGA). The debinding kinetics of the stearic acid/polystyrene binder have been described using model free methods and compared with the decomposition rate of the pure polymers. The apparent activation energy Eα as a function of...

Université de Fribourg

A case study of the effect of grain size on the oxygen permeation flux of BSCF disk-shaped membrane fabricated by thermoplastic processing

Salehi, Mehdi ; Clemens, Frank ; Pfaff, Ewald M. ; Diethelm, Stefan ; Leach, Colin ; Graule, Thomas ; Grobéty, Bernard

In: Journal of Membrane Science, 2011, vol. 382, no. 1-2, p. 186-193

Oxygen permeability measurements of Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) disk shaped membranes fabricated by thermoplastic processing and sintered at different temperatures (1000–1100 °C), showed no influence of the grain size on the oxygen permeation fluxes. To further investigations, Electron Backscattered Diffraction (EBSD) and...