Chromatography Forum

Hello everyone,
I work with a GC-MS agilent and headspace sampler, usually I analyze DMF (N,N-Dimethylformamide) with a vf-wax column. I would like replace column with another kind where I can set the gc-oven until the max temperature of 300°C. I have tried the hp-5ms but it doesn't get peaks with gaussian shape. Do you have any suggestion about the right column for my purposes? VF-Wax is good, but I looking for higher temperature limit
Thank you,
Francesco M.

Hi Nitroarrow,

Try this as an idea:

https://www.agilent.com/en/products/gas ... for-amines

Sounds like you need a base-deactivated column...this will fit the bill...temp max is 350 degrees Celsius.

Best Wishes!

And here is a second idea:

https://www.agilent.com/cs/library/appl ... 9726EN.pdf

DB-1301.

Thank you Matt,
the CP-Sil 8 CB is very interesting!!
the best wold be arrive to 310°C and it seem the right column.

But for the Wax type (polyethylene glycol phase) aren't there column that arrived similar temperature?

Hi Nitroarrow,

I'm afraid not. These PEG-based wax stationary phases are promised to tolerate no more than 260 - 280 degrees Celsius...if you seek more than 300 degrees, it is best to try another phase, I think.

Matt is correct. You'll never find a wax phase that will go that hot. It is pretty likely that your DMF won't interact as well with phases other than a wax. Peak shape won't be as good:

https://1drv.ms/b/s!AkH-uI0tnY5Le9xJJRT0XkjQy7E

Thank you rb6banjo, I'm looking for other kinf of column because in my instrument there is another column join with ALS, where normally it works until 300 °C and each time that I use it I have to disassemble the wax column

Why do you need to go to such high temperatures ? If you are doing headspace analysis nothing that you put onto the column is very heavy and so it should not need high temperature to elute. If it is an issue of the time that it takes to elute the last peak, then try a thinner stationary phase, or better still a shorter column.

The same question and strategy applies to the other column - you may be able to avoid the high temperatures with a thinner phase or shorter column. Don't let the default 30 m 0.5 micron column paint you into a corner.

Peter