Hydrogen permeation through carbon-carbon composites

[RandomGuy88]

I am attempting to find information about the permeation of hydrogen through carbon fiber reinforced carbon composites and was wondering if anyone could provide some help. I don't have many details to provide. We are in the early stages of a research project in which hydrogen may be flowing through channels made of a carbon-carbon composite and I would like to make some estimates of hydrogen permeation through this material.

Any help would be appreciated.
Thanks

 

[trurle]

I am attempting to find information about the permeation of hydrogen through carbon fiber reinforced carbon composites and was wondering if anyone could provide some help. I don't have many details to provide. We are in the early stages of a research project in which hydrogen may be flowing through channels made of a carbon-carbon composite and I would like to make some estimates of hydrogen permeation through this material.

Any help would be appreciated.
Thanks

Carbon fibers itself are porous (10-20% micro-porosity typical) and do not represent an effective gas barrier. Also, carbon-carbon composites may have macro-porocity, depending on construction of composite plies. Overall, you can realistically expect it leaking hydrogen in copious amount.

 

[RandomGuy88]

Carbon fibers itself are porous (10-20% micro-porosity typical) and do not represent an effective gas barrier. Also, carbon-carbon composites may have macro-porocity, depending on construction of composite plies. Overall, you can realistically expect it leaking hydrogen in copious amount.

Thank you, this is very helpful. Would you happen to know of any sources that may provide this information?

Would you expect the carbon-carbon composites to be ineffective at containing any gas? Do you know of any coatings that can be applied (at very high temperatures ~3000K) that may work?

 

[trurle]

Thank you, this is very helpful. Would you happen to know of any sources that may provide this information?

Would you expect the carbon-carbon composites to be ineffective at containing any gas? Do you know of any coatings that can be applied (at very high temperatures ~3000K) that may work?

I remember some presentations on conference about silicon carbide coating over carbon for the high-temperature gas barrier function. The thickness of coating to be effective was 3mm. The main problem was coating cracking. Sorry, do not remember exact reference.

Regarding 3000K temperature, performance of C/C composite is largely unknown. The test setup is too difficult to make.
For up to 2500C see
http://www.iccm-central.org/Proceedings/ICCM17proceedings/Themes/Materials/CARBON - CARBON COMPOSITES/D3.6 Kobayashi.pdf

Regarding "carbon-carbon composites to be ineffective at containing any gas" statement, it depends on acceptable leakage rates and application. Definitely the design without any drainage of leaked gas would not work. Design with chemical getter may work for some time (likely minutes in rocket motor-like applications). Design with non-enclosed space or pumped vacuum on other side of carbon-carbon conduit will likely be an acceptable solution. Could you be more specific about your application?

 

[Astronuc]

I am attempting to find information about the permeation of hydrogen through carbon fiber reinforced carbon composites and was wondering if anyone could provide some help. I don't have many details to provide. We are in the early stages of a research project in which hydrogen may be flowing through channels made of a carbon-carbon composite and I would like to make some estimates of hydrogen permeation through this material.

This might help - https://www.osti.gov/servlets/purl/1249338

There may be such an article in https://www.journals.elsevier.com/international-journal-of-hydrogen-energy - however, I am not aware of such an article.

I believe in most cases, different groups are looking for coatings to protect the carbon-fiber composites. SiC is one such possibility.

Another example - https://avs.scitation.org/doi/abs/10.1116/1.4977106?journalCode=jva

 

[Tom.G]

For a wider search try:
https://www.google.com/search?&q=carbon+fiber+hydrogen+storage+tanks

Or even wider:
In the Google search, enter: carbon fiber hydrogen
And it will give suggested search phrases.

Cheers,
Tom