NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Variable-temperature cryogenic trap for the separation of gas mixturesThe paper describes a continuous variable-temperature U-shaped cold trap which can both purify vacuum-line combustion products for subsequent stable isotopic analysis and isolate the methane and ethane constituents of natural gases. The canister containing the trap is submerged in liquid nitrogen, and, as the gas cools, the gas mixture components condense sequentially according to their relative vapor pressures. After the about 12 min required for the bottom of the trap to reach the liquid-nitrogen temperature, passage of electric current through the resistance wire wrapped around the tubing covering the U-trap permits distillation of successive gas components at optimal temperatures. Data on the separation achieved for two mixtures, the first being typical vacuum-line combustion products of geochemical samples such as rocks and the second being natural gas, are presented, and the thermal behavior and power consumption are reported.
Document ID
19780069516
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Des Marais, D. J.
(NASA Ames Research Center Extraterrestrial Biology Div., Moffett Field, Calif., United States)
Date Acquired
August 9, 2013
Publication Date
August 1, 1978
Publication Information
Publication: Analytical Chemistry
Volume: 50
Issue: 9, Au
Subject Category
Engineering (General)
Accession Number
78A53425
Funding Number(s)
CONTRACT_GRANT: NGR-05-007-221
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available