ssdd - 17-7-2009 at 16:08
The past several weeks I have been working on a Shimadzu GC-17A for separating fatty acid methyl esters. For this I installed a proper column and
wrote a method that so far has given me good results.
Lately the FID being used started acting up, we replaced the hydrogen injector after this started with no avail.
When 1uL of FAME dissolved in benzene is injected into the GC the benzene comes out after about 1 minute, normally this peak passes and data continues
to come out, but now the FID shuts off when the benzene peak hits its max and no further data (other than a flat line) is obtained. As mentioned the
hydrogen injector was replaced and the jet area cleaned. So I was wondering what could possibly going on? (and once again the method and column worked
before and have not changed since this started)
Thanks for any advice,
-ssdd
ProChem - 21-7-2009 at 04:56
if it is a flame problem; first check the temperature of the detector. it should be at least 220C then check your air to hydrogen ratio. if there is
not enough air for the analyte it will extinguish the flame. If that dosen't help then clean the detector jet / collector. If the power to the
detector shuts off then there may be a gas leak.
[Edited on 21-7-2009 by ProChem]