when you add the acid to the methanol, how do you prevent the boiling when the two come incontact. I add the acid to the methanol very slowly, but I still get a bit of boiling. Does this affect the acid ester? Also will their be any fallout after mixing the acid ester into the oil ,like glycerine?

Will water in the oil stop this reaction? I have tried a few small samples and after mixing for 1.5 hours and sitting for 24 the titration did not change. A boil test showed water.

quote:

Originally posted by dingo0722:
when you add the acid to the methanol, how do you prevent the boiling when the two come incontact. I add the acid to the methanol very slowly, but I still get a bit of boiling. Does this affect the acid ester? Also will their be any fallout after mixing the acid ester into the oil ,like glycerine?

Will water in the oil stop this reaction? I have tried a few small samples and after mixing for 1.5 hours and sitting for 24 the titration did not change. A boil test showed water.

Adding acid to the methanol needs to be done slowly, it will generate heat.
What amounts are you talking about how much acid and how much methanol. What is your starting titraton.

With regard to water, yes it is your enemy in the Esterification reaction the water that is created during the reaction will eventually stop the reactin, if there is water in the oil to start with it will reach that point sooner.

Starting titration of 11 using KOH. I was adding 300ml(2ml/gallon) to 4 gallons meth which was added to 40 gallons of oil.

It seems even when I add the acid slowly, there still is a boiling reation. Is this normal? Does some fog/gas always form above the methanol. Does this reduce the potency.

Where do people buy their acid. I was getting it from Alfa Aesar but it is expensive

I used an explosion-proof mixer to stir the methanol vigourously and I still got a 'fog' of methanol in the drum. I was using a 55 gallon drum to stir up 20 gallons of acid/methanol. However, the boiling is very localized at the point where the drop of acid falls, so it's not like an 'overheat' type of boiling. A methanol fog forms above the surface of the methanol and sits there. A good bearing or gasket for the mixer propeller is important.

Other people here have just used 15 gallon drums to add the acid to 6-8 gallons of methanol. It's not as safe as stirring the methanol but the mostly-closed drum keeps the fog in, mostly. It's a compromise. I'll be going back to this method this winter and will probably use a 55 gallon drum (with a valve at the bottom) to passively add acid to relatively small amounts of methanol and just call it good, my new shop is well-ventilated (ie I'm working mostly outdoors)