I was developing a GC-FID method using methylene chloride as a solvent. My boss asked me why and he said MeCl2 doesn't burn. I don't know the reason. Anybody knows?
By Anonymous on Tuesday, March 23, 2004 - 05:38 am:
Methylene Chloride burns in my universe. Which universe does your boss live in?
Methylene Chloride is a volatile solvent and elutes quickly compared to many solvents, although not the best for some applications.
Let your boss see the orange flame and the soot as the solvent elutes in the FID, perhaps then he will believe.
By mgoodwin on Wednesday, March 24, 2004 - 06:08 am:
Methylene chloride is a nonflammable liquid. You still see a signal in the FID, but it's considered a low response compared to hydrocarbons.
Choice of solvent should be determined by
A) how well does it dissolve your intended analyte, and if needed, can be evaporated readily to desired concentration.
B) does not react with your sample
C) how well does it NOT dissolve the non volatile junk that could sit in your GC after analysis, and
D) will not co-elute over peaks of interest or elute irregularly.
Disadvantages of methylene chloride are:
can degrade the seal in your syringe
is considered a carcinogenic suspect...
on a side note: should you see soot coming from your FID, check your air/hydrogen gas flow rates.