How select column to analyse CO,CO2,CH4,C2H6,C2H4,C3H8,C3H6;

[gongchke]

How select column to analyse CO,CO2,CH4,C2H6,C2H4,C3H8,C3H6;and how select the interior standard.thank you very much.

[krickos]

Hi

I think we need a little more information about what type of samples you are running.

Even though my experiance of gas analysis is a bit limited a GS-gaspro column from Agilent/J&W would resolve the gases you talk about. Although I am unsure you can get separation of all those gases at ambient temperature. You might need to have a cryo function on the GC oven to make it work on this column.
Unless someone else comes up with a better column choice or you might need to split the injection to two different columns.

Sigma Aldrisch has a bunch of standards including gases, but unsure if it suits your purposes but worthwhile to check out.

Good Luck

[jeputnam]

I've used PLOT type columns to analyze these gases. They function similarly to molecular seives. The gases enter pores and are held there. They are released as the temperature is increased. I didn't need cryo temperatures. The starting temperature was just above ambient.

[AICMM]

gongchke,

One possible column for you to think about is the ShinCarb from Restek. I have a couple of customers using it with good results although you might have to pay attention to the elution of water from the column. If appropriately temperature ramped, it can easily do C2 hydrocarbons and probably C3 hydrocarbons while still separating H2, O2, and N2.

Regarding internal standard, if you are not sampling continuously, then I think you are going to have a very difficult time doing an IS. Most gas analysis I have seen/done is based on external standard calibration with the mixes that krickos refers to.

Best regards.