Single Column for Digester Gas Separation

[pepper031859]

I'm trying to find a single column (capillary) that will separate out the following gases: CO2 H2S N2 CH4. The problem is the getting all four. I was using a very old GC with packed columns (two sets). Some one said to me that they had heard of a column within a column. I never heard of this before and haven't been able to find any thing like online. Any help?

[chromatographer1]

There is no problem in separating these gases with a single column.

I would use a micropacked column of Hayesep D or Porapak Q.

The critical issue is the tight separation of N2 and Methane for large of concentrations at the same time, but CO2 and H2S easily separate from the other two. I would suggest a column of at least 6 meters.

A single capillary column could also be tried. If you are trying to measure ppm levels of H2S then special packings and capillaries are required.

For a better answer try to give a bit more information as far as concentrations and a listing of other possible interferences.

best wishes,

Rod