Testing CF4 by FID GC

[jwlee]

Hello,

I'm trying to test carbon tetrafluoride (R-14) by FID GC, but I can't get any sort of significant peak. The area of the curve is about 100 at best, and I've tried it on multiple FID instruments with the same result. I'm regulating the pressure down to about 20 psi and using a 6-port autosampler.

Any thought would be much appreciated.

[Peter Apps]

I doubt that this can be done; an FID responds to C-H bonds and to a lesser extent C-C bonds. Your molecule has neither.

Peter

[chromatographer1]

I am not surprised by the lack of response. I suppose you are using capillary columns.

Usually packed columns with a much larger sample size are used if a FID is employed.

Do you have any other detector available?

Rod

[jwlee]

I have a TCD/DID, but because CF4 elutes so close to nitrogen on the TCD, I wanted to confirm that is UHP CF4, since N2 won't show up on the FID. I'm using a ss packed column right now.

[chromatographer1]

Are you using a MS13X? Or some other packing? Like a porous polymer?

Rod