Application of a Sol-Gel Based Nanostructured Ceramic Membrane for Hydrogen Separation in CO2 Capture Purposes
bookPart
The two most significant industrial processes for hydrogen production from fossil fuels are coal gasification and steam reforming of natural gas. A membrane process for CO2-H2 separation is an attractive alternative to conventional technologies such as solvent scrubbing, pressure swing adsorption, and cryogenic distillation for capturing the CO2. The advantages of using membrane reactors, i.e., the combination of a chemical reactor and membrane separation as one unit operation, are highly evident, e.g., the possibility to shift the chemical equilibrium towards the product side, the improvement of hydrogen production, along with high fossil fuel conversion at milder operating conditions and thus a lower efficiency penalty and lower cost. In principle, two different types of membranes are under development, dense Pd-alloy based and porous inorganic ceramic ones. The non-metallic inorganic membranes are in principle more robust, thermally and mechanically, but suffer from the drawback that the pore size has to be tuned to the kinetic diameter of hydrogen in order to obtain sufficient selectivity, for instance by Atomic Layer Deposition (ALD). The present contribution provides a literature overview of ceramic membranes and their performance which are currently under investigation for hydrogen separation at high temperatures, as well as recent research results by the authors. The scope of materials presented here is limited to those that are primarily based on sol-gel synthesis.
TNO Identifier
847578
Publisher
ECN
Collation
52 p.
Place of publication
Petten
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