Chromatography Forum

Dear All,

Ever since conditioning the new column, every time the column is heated at higher temperatures than say 100 C and up to its higher limit which is 320 C (actual is 325 C according to manufacturer), the column smells!
The higher the temperature, the stronger it smells. Has anyone encountered this or heard of it?
The column smells the same whether there is a sample being run or just a blank. I should also mention that there is column bleed evident even with this new column (only after a few injections) but I think that is not unusual (?). I am newbie on this.

Any insights are welcome.

Thank you,

Ontherun

Quick answer.

Return the column to the manufacturer for a refund.

What column is this?

Rod

Thank you for your answer Rod, the column is a 100% Dimethylpolysiloxane, 30 m, 0.25 mm and 0.25 um.

There should be no odor unless the chemistry did not work as it was supposed to work.

The company needs the column as is so they can verify the problem and you can get another column free, or your money back.

Do not bake it out hoping for better results. Send it back.

Rod

Ever since conditioning the new column, every time the column is heated at higher temperatures than say 100 C and up to its higher limit which is 320 C (actual is 325 C according to manufacturer), the column smells!

So what's the highest oven temperature you run?

Ya' sure it's not the GC oven itself that is smelly? Or the GC fan motor?

We have one GC where someone at a production facility used house air (from an oil-lubed compressor) to supply air to the FID as a cost savings idea. When the GC was shipped to R&D, there mustive been like 20 ml of oil in the FID controls, the FID itself, and in the GC oven insulation on top of the oven (5890). We swapped in controls and FID from older parts GC, tore out most of the insulation that was oil-contaminated and replaced with fiberglass tape, and now we use that GC for specialty applications, and don't take it over 190C as it would smell horrible !!!

Presumably this is a problem with the polyimides coating on the outside of the column, which is certainly a problem for the manufacturer, but as an ouside chance check that there was not a paper or plastic label accidentally left attached.

Peter

Dear All,

Thank you for your answers. I am sure there is no strange material inside the oven other than the column. As for the FID case mentioned, that is interesting and useful to know. As for oven insulation, the only insulation I added before trying this column is brand-new quartz wool but this is made to withstand temperatures higher than 900 C and it is used in clean environments so this should not be the source of the odour. The amount I had to pack in was minimal just to cover one of the ports to a detector (for instance where the FID would go, this is a GCMS which was interfaced to another instrument).

I guess the only way to know the source of the problem is by trying a new column from a DIFFERENT manufacturer but with the same stationary phase. Which is what I am doing next as I am definitely returning this one.

Ontherun

So what's the highest oven temperature you run?[/quote]

200-320 C

Dear All,

Ever since conditioning the new column, every time the column is heated at higher temperatures than say 100 C and up to its higher limit which is 320 C (actual is 325 C according to manufacturer), the column smells!
The higher the temperature, the stronger it smells. Has anyone encountered this or heard of it?
The column smells the same whether there is a sample being run or just a blank. I should also mention that there is column bleed evident even with this new column (only after a few injections) but I think that is not unusual (?). I am newbie on this.

Any insights are welcome.

Thank you,

Ontherun

Good night. Sorry, this is in Moscow night. Hi

Odor when heated columns to the critical phase temperature - this is normal. For all columns. For capillary-MS is smaller / but for packed stronger. Evaporate monomers.
Evaporation of monomers are harmful to health, since the combustion of soot (many phases such apiezonu) or a spray of silicon oxide (siloxane phase). We install box of Plexiglas or metal on the detectors , and evacuated the products of combustion in the dry box/

Fanaticism is not needed. Frequency and time of heating the column depend on the analytical task, noise and artifact peaks. The phase temperture must not exceed the recommended limits
PS
I'm shocked. I thought that in your countries all described a supervisor in the standard procedure.

So what's the highest oven temperature you run?
200-320 C

Methylsiloxane phases (such as G1-USP ) ?
Any another phase distruction is high in 320 C temperature

Dear Friend

Could you please mention which specific brand column you use ? Also mention full specification of the same like length , ID , thickness , Maxi workable Temp. , Maxi Temp. etc...

Hope you must have received literature for Column conditioning alongwith your purchased column & conditioning would have been initiated as per literature you received . Ryt ?

GC column conditioning:
Install the column to the injector. Do not connect the column to the detector. Leave the column end in the GC oven.
Set the GC oven to 40°C
Hold this temperature 15 minutes
Set the temperature gradient to 10°C/min
Set the maximum operation temperature 20°C above your final temperature of the GC temperature program (the maximum temerature must be 25°C below the column maximum operating temperature)*
Leave the column at high temperature ovenight until the baseline stabilizes. If the column is pre-conditioned, leave tha maximum temperature for 2 hours and untill the baseline stabilizes.

Overnight conditioning is only recommended in a few situations. When a column will be used at its maximum operating temperature limit for extended periods of time (such as with simulated distillation analysis), or when a thick-film column will be coupled to a very high sensitivity detector (such as an electron capture detector or mass spectrometer), overnight conditioning might be necessary to achieve a stable baseline. Note, however, that operating capillary columns at their maximum temperatures over a long period of time will shorten the lifetime of the column.

Hope this will help . If doesnot , I think column manufacturer / supplier should be contacted .