Gases filtration/separation in metallic membranes
Application
What is it?
Gas separation of emissions in CO2 or H2
Potential solution to reduce greenhouse gas emissions
Mostly used membranes in the process: Palladium
How it works
Separation due to diffusion mechanism
How does it work?
H2 molecules adsorption from the membrane side at higher H2 partial pressure
Dissociation of H2 molecules on the surface
Reversible dissociative chemisorption of atomic H2
Reversible dissolution of atomic H2 in the metal lattice of the membrane
Diffusion into the metal of atomic H2 proceeds from the side of the membrane at a higher H2 pressure to the side at lower pressure
Desorption of recombined atomic H2 into molecular form
Due to higher permeability of hydrogen
Membrane alternatives: dense membranes, such as Ni, Ta, Va, Zr, Pd, Ag
Axiom selects polymide membrane
this depends of the customer requierements
certain membranes can be operated at temperatures as high as 100°C
Techniques
Chemical vapour deposition
Thermal sintering
Electroplating
Template-direct synthesis
Casting
De-alloying
Electro-spinning
Wet casting/coating
Ink-jet printing
Electrical sintering
Gas mixtures can be effectively separated by synthetic membranes made from polymers such as polyamide or cellulose acetate, or from ceramic materials.
Electroless deposition
Block co-polymer
they act as a permeable barrier through which different compounds move across at different rates or not move at all.
The membranes can be nanoporous, polymer, etc. and the gas molecules penetrate according to their size, diffusivity, or solubility.
many emerging membrane applications involve the separation and/or the filtration of higher strength contaminant loads or abrasive particles in waste concentrate streams or slurries, or processing of gas and vapours, and require porous or dense membranes with robust mechanical properties, and high thermal and chemical stability.
References
Sotiris, P., Grigoris, T., Dimitris, E.. (2018). Chapter 12 - Membrane Technology in IGCC Processes for Precombustion CO2 Capture. Current Trends and Future Developments on (Bio-) Membranes, Elsevier, Pages 329-357, ISBN 9780128136454, https://doi.org/10.1016/B978-0-12-813645-4.00012-X.
Colin A. Scholes, Kathryn H. Smith, Sandra E. Kentish, Geoff W. Stevens. (s.f.). CO2 capture from Pre-combustion Processes - Strategies for membrane gas. Greenhouse Gas Technologies (CO2CRC) Department of Chemical and Biomolecular Engineering, University of Melbourne, Parkville,VIC, 3010, Australia. Retrieved from https://minerva-access.unimelb.edu.au/bitstream/handle/11343/129836/H2_Mem_Review_Paper_reviewed_final.pdf?sequence=1&isAllowed=y
Zhu, B., Duke, M., Dumée, L., Merenda, A., Ligneris, E., Kong, L., Hodgson, P., and Gray, S. (2018). Short Review on Porous Metal Membranes—Fabrication, Commercial Products, and Applications. Membranes (Basel). 8(3): 83.
doi: 10.3390/membranes8030083
Axiom. (2021). GAS SEPARATION TECHNOLOGY. Retrieved from https://www.axiom.at/gas-separation-technology/
Schürmann, A., Haas, R., Murat, M., Kuritz, N., Balaish, M., Ein-Eli, Y., Janek, J., Natan, A., and Schröder, D. (2018). ECS.
Journal of The Electrochemical Society, Volume 165, Number 13. Electrochem. Soc. 165 A3095
Science Direct. (s.f.). Dense Metallic Membrane. Retrieved from https://www.sciencedirect.com/topics/engineering/dense-metallic-membrane