Gettering of Hydrogen and Methane from a Helium Gas Mixture

Journal Article · Tue Oct 21 00:00:00 EDT 2014 · Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films

DOI:https://doi.org/10.1116/1.4898204· OSTI ID:1183093

Cardenas, Rosa E. ^[1]; Stewart, Kenneth D. ^[2]; Cowgill, Donald F. ^[2]

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1. Univ. of the Incarnate Word, San Antonio, TX (United States)
2. Sandia National Lab. (SNL-CA), Livermore, CA (United States)

In our study, the authors developed an approach for accurately quantifying the helium content in a gas mixture also containing hydrogen and methane using commercially available getters. The authors performed a systematic study to examine how both H2 and CH4 can be removed simultaneously from the mixture using two SAES St 172® getters operating at different temperatures. The remaining He within the gas mixture can then be measured directly using a capacitance manometer. Moreover, the optimum combination involved operating one getter at 650°C to decompose the methane, and the second at 110°C to remove the hydrogen. Finally, this approach eliminated the need to reactivate the getters between measurements, thereby enabling multiple measurements to be made within a short time interval, with accuracy better than 1%. The authors anticipate that such an approach will be particularly useful for quantifying the He-3 in mixtures that include tritium, tritiated methane, and helium-3. The presence of tritiated methane, generated by tritium activity, often complicates such measurements.

• Research Organization: Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: AC04-94AL85000
• OSTI ID: 1183093
• Alternate ID(s): OSTI ID: 22317927
• Report Number(s): SAND2014--16893J; 536876
• Journal Information: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films, Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films Journal Issue: 6 Vol. 32; ISSN 0734-2101
• Publisher: American Vacuum Society
• Country of Publication: United States
• Language: English