what is a suitable column?

[new future]

Hi there

If the sample contains H2 as a major gas and CO2, what is the suitable cloumn as I am interested in H2 only?
I have used a packed column (molecular sieve 13X) but I heared this is not suitable to analyze H2 in presence of CO2..

[chromatographer1]

I cannot imagine why it would not be suitable.

Any explanation?

Carboxen 1000 column would work, as well as, almost any porous polymer column if made in a suitable length.

CO2 doesn't damage a MS13X. Will you use a backflush valve?

best wishes,

Rod

[new future]

Thank you very much chromatographer1

The GC technician told me the separation of H2 will be poorer in presence of CO2 in the same sample if I use the packed column (Molsev 13X), so I should use any Hayesep column.

What do you think about that??

[chromatographer1]

I would suggest a long porous polymer column either, Waters Porapak, VICI Hayesep, or a Chromosorb Century Series from Celite.

While a 13x will work, a Carboxen 1000 will also work better (although CO2 will take some time to elute),

Almost any of the porous polymers will work (Chromosorb 102, Hayesep D, and Porapak QS would be the best choices) but will take some time for CO2 to elute, but less than the Carboxen 1000.

Water will not effect the Carboxen 1000 or the porous polymers if that is a factor. Just remember that it will take a LOT of column (9m?) to separate He or other noble gases from Hydrogen on a porous polymer micropacked column. Less column is required for the Carboxen 1000 column. (2m?)

Column length is dependent upon the temperature you chose to operate. The above recommendations assume a 60 to 80°C oven temperature range.

best wishes,

Rodney George
Senior Research and Development Scientist
Gas Separations Research
Supelco
595 North Harrison Road
Bellefonte, PA 16823

814-359-5737 voice
814-359-5459 fax
rgeorge@sial.com