Chromatography Forum

I search a column to separate H2-O2-N2-CH4-CO2-CO(0-100 ppm for each impurities) in background helium or Argon.
Carrier gas will be helium or Argon(about 30CC/min)

I know I can use Molecular Sieve 5A 60/60 for H2-O2-N2-CH4-CO and a Porapak Q for CO2.
But I want one column to do all the impurities in the same column.

Please let me know which column use.

Best Regards

Carboxen 1004 in a (2-4m?) 1/16" OD micropacked column (0.040" ID) or Carboxen 1000 in a (4-9m?) 1/8" OD column (0.084" ID) will perform the analysis you want, depending upon temperature requirements. I would recommend that screens be used to minimize dead space in the chromatography system and improve separations. A TCD or PHID, of course, will be needed as well as a gas sampling valve.

A less desirable alternative in some ways would be to use a Molecular Sieve 13X column.

You may email me for more details.

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

I have similar problem (N2+H2+CO+CO2) carrier gas He or Ar, but I also have to separate H2O. Which packed column you recommend?
Regards

If separation only is required, the Molecular Sieve 13X will absorb the water quite effectively for a period of time before it needs to be reconditioned. A large water plug may not be completely absorbed at each injection.

The two Carboxen columns will elute the water but requires you to elevate the temperature of the column above ambient to achieve a reasonable peak shape. Either is suitable.

If you want to measure the water in trace amounts, then be certain to use glass columns or FSOT coated SS columns.

Be sure you order the 5 or 10µ SS screen column terminations and not the SS frits.

Another good, single column solution would be a Restek ShinCarbon ST http://www.restek.com/fantasia/pdfCache/59519a.pdf . Water would elute after the Carbon Dioxide. Unlike the MSieve column, as long as the water is allowed to elute after every analysis (max column temp is 330C), you will not need to worry about reconditioning the packing.

Read this with interest.

Am currently using an packed RTX and Molysieve in the same oven.

This was originally for % level work in gas efluents with a mix of Argon (on RTX) and Helium (on MS) columns.

TC detection on Agilent 6890 using Galaxie CDS.

Now I'm trying helium only to do ppm levels in C3H6.

This has been OK but a cap column would be better, will give this atlernative a try

Hello, In fact it should be known that recently varian markets a column made up of 2 columns in series (molsieves and porabond Q connected by a quick seal) which is called "Select Permanent Gases/CO2". Favours: there does not need more to use a switching system of valve