Im working with ethanol. somebody can tell me how to analyze ethyl ester with GC? what standard solution i have to use? many thanks

You would do it the same way as for methyl esters. The peaks might look a tiny bit different but they're in the same place.

If you're asking about setting up a GC for the biodiesel conversion analysis, the method you're looking for is the ASTM 6585 method. It takes a machine with:
FID detector
cool on column injector
high-temperature column that goes to 380C (I think, I'm typing this from memory)
hydrogen, ultrapure compressed air, and helium I believe.

thanks alot girl mark. im was bit confused before. I run ethyl ester analyze with BSI standard BS EN 14103 which is basically used for methyl ester. i think the method quite similar to ASTM 6585. many thanks.

hi! i tried to search for downloadable copy of ASTM 6585 from the internet but it seems it is used for plastics. is there any way i can acquire ASTM for ester conversion in biodiesel? i need it for my thesis. thank alot!

by the way, ASTM or EN method for ester conversion suitable for coconut oil fatty acid which is C12-C14. thanks!

To clarify...

ASTM D6584 is the method for quantifying free and total glycerin in B100 via GC.

It is (as Mark points out) a cool on-column injection method.

It seems to work fine for measuring residual glycerin (free and bound) in ethyl esters.

But, since the peak identification for bound glycerin (mono's, di's and tri's) are based on fats and oils containing predominately C16 and C18 chain lengths, you will need to adjust your peak identifications accordingly.

The standard states "This test method provides for the quantitative determination of free and total glycerin in B-100 methyl esters by gas chromatography. The range of detection for free glycerin is 0.005 to 0.05 mass %, and total glycerin from 0.05 to 0.5 mass%.
This procedure is not applicable to vegetable oil methyl esters obtained from lauric oils, such as coconut oil and palmkernel oil.

You should use a different set of standards for mono's, di's, and tri's consisting of lauric and myristic acids (C12 and C14) to get good results.

Just my $0.02

Bob in Moncure