I had to post this quickly before I forget...

I recently collected a sample of home made BioD from a friend.
I've been wanting to analyize this stuff using the tools at work and I finally
got a chance. This is just part 1 of a two part analysis. I hope to do the rest
next week.

Using the FTIR (Fourier Transform Infared Spectroscoper) I came up with
Methyl Oleate.
http://www.thegoodscentscompany.com/data/rw1260141.html
Basically an ester with a looong hydrocarbon chain attached. (see link)
The match was really good, 97%. A residual search turned up Cottonseed oil,
65% match. Not bad considering there wasn't much of a residual to look at.
(residual searches dont really mean a whole lot, so take it with a grain of salt)

I was primarily looking for the presence of water and alcohol. This is easy to
see because any -OH compounds will show a huge-broad peak in the
2500-3000 range.
Anyway, this was not present. Doesn't mean it not there, but not in any
significant abundance that can be measured with this instrument.

The FTIR only sees the stretching and bending of covalent bonds. Sodium
(Na) and Potassium (K) typically bond ionically, so if any were present I
wouldn't be able to see it anyway. But, if there was any NaOH or KOH then
I should be able to see the -OH part, which again wasn't seen.

The FTIR analyizes the the material as a whole and does not have the ability
to separate mixtures. I consider BioDiesel, like all types of fuel, to be a mixture
of different types of Hydrocarbons. The high percent match indicates that a
huge majortity of the stuff is Methyl Oleate. What that other 3% is, I can't
tell you yet. That is part 2, the GC/MS.

Disclaimer: I am not a chemist nor a spectroscopist, just a well trained
equipment user.

_________________
U.S. Army Retired

Sounds like you have quality stuff. Only in poorly washed fuel will you find water, soaps, salts or alcohol.

The other molecules commonly found in biodiesel are methyl linoleate, methyl stearate, methyl laurate and methyl palmitate. There are many others as well.

_________________
'05 Liberty CRD B100, SEGR - SOLD

'01 Beetle TDi B100, EGR delete
'83 Mercedes 240D B100, no EGR

--- SEGR Builder ---

the only reason you find other types of methyl oleate would to other types of oil used to make the BD.

otherwise I agree with UFO's comments.

by the way my wife's liberty like the BD. now using B100. gone through 1 filter to date. this was expected.

-dkenny

_________________
84 BB school bus, DD8.2L turbo ->the transmission died..too expensive to fix..it'll be heading to the scrap yard..4/11)..Bus gone to Scarp 8/23/11
06 Liberty CRD
'99 dodge ram 2500 quad cab, 4x4, 24v
all Biodiesel powered when its warm enough

Wow, Cool

I was afraid no one would know what I was talking about.
Seriously, I didn't know what I would find. I knew it would be some sort
of ester but other than that I had no clue.

All those other esters you mentioned showed up on the list of similar compounds.
They were all virtually indistinguishable when compared to the sample. So
I just went with the best match.
So its possible that its a mixture of more than one ester. The GC/MS will
do a better job of separating the different compounds.

_________________
U.S. Army Retired