We had a de-methed glycerin sample tested by a lab. The results are interesting. Not sure what everything means.

Moisture, Karl-Fischr........... 5.70 %
Dry Matter...................... 94.30 %
Protein, Crude...........Less than 0.1 %
Fiber, Crude.............Less than 0.2 %
Fat By Acid-Hydrolysis........... 32.7 %
Ash.............................. 5.34 %
TSI-Total Sugars as Invert........ 2.9 %
Methanol......................... 0.89 %

Little surprised by the methanol number. Glycerin was heated to 220F under 19 inches of vacuum over night.

is that equivalent to heating it to 260F at no vacuum?

Thanks for posting those Matt

fuelfarmer,
Great information!
Did they suggest which part would be soaps and which part would be glycerol?
What makes up the "Dry Matter"? Is it a summary of some of the items listed?

Do you know if the Fat By Acid-Hydrolysis is the fatty acids from the soaps?

This message has been edited. Last edited by: Rick K,

Just so you know I am not Matt. I would hate to besmirch his good name.

I don't know the equivalent of temp. versus vacuum.

Dry matter is what is left after the water is removed. Feed samples often show results based on "as is" and "dry matter".

I was hoping to get a PH number also.

I listed all the info I got. I plan to make a call and ask some questions.

I'm also surprised by the methanol total.
Your demething process sounds like alot of us.

I'm thinking it would be better to get the residual methanol amount lower before soap making with it. Even though much more methanol is evaporated in the soaping process.
Would spray drying or bubbling the glycerine get the residual methanol number down alot lower?

I need to send off another sample. It is possible that the sample came from the bottom of the batch and had a higher reading. I was told it should be .075% or lower.

The fat, 32.7%, was higher than I expected. Maybe that is why it makes good soap.

What kind of glycerine volume are we looking at for the overnight distill ? I bring my pot temps up to 265F all day (8-4) for 30-32 Lt's glyc and all that is coming out of the drip tube is EXTREMELY slow drips. If I cannot distill it to that point it gets categorised as "trash" and discarded.

And yes, the higher "fats" in the equasion gives you better soap making properties; the formula for true soap is: an acid (oil or fat), caustic (sodium/potassium hydroxude) and water. Scenst are not an essential part of soap, they just make soap more pleasurable.

100 gallon batches. I run up to 220f for 10 to 12 hrs at atmospheric pressure and then pull 19 inches vacuum for another 12 to 15 hrs.

We do about 35-45 gallons at a shot and it takes more than 24 hours to get our pot temp up to 260F where the methanol is barely dripping out of the condensor...

sorry for the mistake on the name FUELfarmer