Which solvent suitable for wax analysis?

[mimrumo]

Which solvent suitable for wax analysis?
I want to analyse wax with GC /FID.My sample is wax and I want to analyse c4-c40 in wax.
I try CS2 but some of them cannot dissolve.

Need your help.

[chromatographer1]

C4-C8 may not be possible in any solvent that will dissolve C40-C52

Two injections with two dissolution solvents with Istd to quantify may be necessary.

best wishes,

Rod

[Consumer Products Guy]

Use hexadecane.

Or use isooctane, and keep the solutions warm before/during injection so the wax does not precipitate out.

[mimrumo]

Thanks for all suggestion.
I will try.

[JGK]

AOCS methods use heptane

[chromatographer1]

C16 or C7 still has interference with the range the analyst was seeking, C4 through C40, with option to go to C52.

This is why I said to use two different solvents: Heptane and hexadecane sound good to me with (ethyl benzene? as) an internal std chosen by the analyst.

best wishes,

Rod

[AICMM]

mimrumo,

Something doesn't quite make sense here. CS2 is the solvent of choice for SimDis including residuals and from C5 to C100. Given a reasonable amount of CS2, all of the sample easily dissolves in the CS2. So, either you are not using enough CS2 or you have something unique that does not want to dissolve in the CS2 (perhaps particulates?) Are you at liberty to more fully define your sample? My other question is: what indication do you have that some of them are not dissolving?

The other advantage to CS2 is that it gives a very small solvent peak which is not the case with all of the other solvents mentioned above. I believe the solvent peak of the other solvents mentioned will make C5 very difficult to quantitiate.

Best regards,

AICMM

[Consumer Products Guy]

Our company's candles do not contain any carbon chains that small, why we can use hexadecane. I have trouble calling stuff with low carbon numbers "waxes".