Chromatography Forum

Hi,

I need to analyze glycols with GC-FID, the compounds appear in EPA 8015 and it says that the extraction is by azeotropic distillation with direct injection of water samples. I have a DB-5, is this a column for this type of injection? i think not.
With this column, can i analyze glycols? If not, what other method or column do you recommend?

Thanks.

It has been done using a DB-5 but a wax column works much better. Limit the injection volume with water.
Simple injection of 0.5 uL should get you to low ppm for ethylene and propylene glycol.

So i can use a DB-5 with direct injection of water but with low volume, is that correct?

Thank you very much.

If your detector is an FID you're going to have a hard time keeping that flame lit after injecting water on a "5" column. Wax columns are what we use. We also found we need to be very aggressive with maintenance after injecting water.

I'm betting your glycols won't give you nice peak shapes with the nonpolar DB-5 phase. The wax is your best bet.