abstract
The electrical performance and CO2 permeation of composite membranes based on Gd-doped ceria skeletons impregnated with molten alkaline carbonates are benchmarked against their predictable performance based on ambipolar conductivity governed kinetics (best scenario), using customized diagrams. Experiments performed in the 550-850 degrees C temperature range showed permeation rates reaching almost 0.6 cm(3) min(-1) cm(-2) at 850 degrees C with 50 mol% CO2 content in the feed side. Endurance tests performed at 650 degrees C for over 100 h showed a small degradation due to microstructural changes. Impedance spectroscopy measurements combined with microstructural analysis involving several composite membranes and skeletons after distinct thermal history confirmed the potential of these techniques to monitor the ceramic skeleton and membrane condition. The diagrams used to map membrane performance highlight in an entirely novel manner several kinetic and experimental constraints.
keywords
CARBON-DIOXIDE SEPARATION; DUAL-PHASE MEMBRANES; MOLTEN-CARBONATE; HIGH-TEMPERATURE; IMPEDANCE SPECTROSCOPY; DOPED CERIA; ELECTROLYTES; PERFORMANCE; PERMEATION; TRANSPORT
subject category
Engineering; Polymer Science
authors
Patricio, SG; Papaioannou, EI; Ray, BM; Metcalfe, IS; Marques, FMB
our authors
Fernando Manuel Bico Marques
Full professor
Sónia Gonçalves Patrício
Assistant ResearcherGroups
G3 - Electrochemical Materials, Interfaces and Coatings
G5 - Biomimetic, Biological and Living Materials
acknowledgements
The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Program (FP/2007-2013)/ERC Grant Agreement Number 320725, from the EPSRC via Grant EP/J016454/1, EP/M01486X/1, EP/P007767/1, EP/P009050/1, via Projects NANOMFC (New-INDIGO/0001/2013), CO2ZERO (POCI-01-0145-FEDER-016654 - PTDC/CTMCER/6732/2014) and CICECO-Aveiro Institute of Materials (Ref. FCT UID/CTM/50011/2013), financed by national funds (Portugal) through the FCT/MEC (PIDDAC) and when appropriate co-financed by FEDER under the COMPETE 2020 Program. S. Patricio thanks FCT for the postdoctoral grant (BPD/75943/2011).