What happens to the methanol?

[nummit]

What happens to the methanol during the reaction process? Does it settle out with the glycerin or does it stay in solution with the final product?
The reason I ask is because I heated the final product to well over the boiling point of the methanol during the drying process.
Did this ruin the bio?

[Spencnaz]

When you mix the methanol and lye together you are making Sodium Methoxide.

In a chemical transesterfication of alcohol and a free fatty acid, this reaction can only take place at a very high temperature. Lye is used as a catalyst to lower the reaction temperature required to make the esterfication happen.

What the methanol does is latch onto the glycerine molecule in the oil and cause it to precipitate out of solution to the bottom of the vessel. So techically, it should be called glycerol to reflect the alcohol chain that is not attached.

Heating your finished biodiesel with the glycerol removed will liberate some trapped methanol that may still be in solution, but that is the reason for bubble washing and/or mist washing, to use water instead of heat to remove the alcohol. Methanol is extremely hygroscopic, meaning it will take on water as fast as it can. Bubble or mist washing is a very safe and effective way to get any residual methanol or glycerol out of the biodiesel before use.

As for your heating your final product for drying, I wouldn't think that it would be an issue, however I wouldn't want to be around catching a whiff of the fumes coming off.

At what temperature are you heating your biodiesel? It's obviously above 64C or 147F. The only other problem I would see is the formation of peroxides in the biodiesel which may cause injector fouling over a period of time, but if you are using the biodiesel right away without long term storage, it shouldn't be an issue.

Hope this helps.