PeachParts Mercedes-Benz Forum - View Single Post

coachgeo · #40 06-16-2004, 11:23 PM

Quote:

Originally posted by TomJ
...
Remember, the glycerine is what is removed (replaced) from the SVO/WVO to make BD, ......

This is NOT correct as you state it here. As stated earlier there is basically no glycerin in SVO/WVO. There is in unwashed/poorly washed biodiesel. That being said let me use the below to clarify this a little more

Quote:

by Habanero:
there should be almost no free glycerine in the (SVO/SVO) oil entering the combustion chamber. What happens at that point, however, may produce free glycerine at some point in the combustion process. I am assuming one of the first steps in the combustion process would be to break apart the glycerol backbone, sort of like making biodiesel. At this point, you would have free glycerine running around that could potentially be formed into acrolein. If, however, during the combustion process the backbone breaks up before the fatty acids are cleaved, then acrolein formation would be impossible.

As far as general composition of SVO goes, I can get exact numbers from my supervisor when she gets back tomorrow, but most refined oils are about 98-99% triglycerides with the remainder made up of bioactive compounds, small amounts of free fatty acids, etc.

It is very difficult to say general composition of WVO, though, since so much depends on how it was used and what was fried in it. It is still going to be mostly triglycerides, but there will be some di and mono glycerides where the fatty acids have broken off the backbone to become free fatty acids.