Methane analysis in H2-CO-CO2-CH4 mixture
Posted: Mon Aug 12, 2013 5:32 pm
I need to analyze methane in H2-CO-CO2-CH4 mixture. Which column can you recommend? I have GC/TCD and He as a carrier gas. Will I see H2 at all?
Probably the best choice would be a molecular sieve 13X, not the 5A, at temperatures below 80C, 40C would be a good choice.
Hydrogen can be seen at levels over 100 ppm or so, depending upon the sample size injected.
Hydrogen will not be linear and accurate measurement into the percent levels will be highly inaccurate.
To measure all accurately a different detector would be necessary.
A 3m packed column is more than adequate. See the vendors chromatograms on the internet or look at their catalogs.
If water is a concern then a 15ft Carboxen 1000 is a good choice. Expect CO2 to elute at 15 minutes at 120C.
I have also posted 'grams previously but they may not be good links at this latter date.
best wishes,
Rod