Hi all!
I've been trying (made 5 batches) to produce biodiesel in a laboratory, for educational purposes. This is what I've been doing:
- 1 liter of virgin oil from supermarket
- 200 mL of methanol
- 3,5 grams of sodium hydroxide
- Prepared the sodium metoxide by stirring for 24 hours (magnetic stirrer) in an closed Erlenmeyer
- Preheated the oil to 55ºC
- Using a flask with an attached Liebig condenser (to prevent methanol vapors to escape), mixed vigorously for 1 hour maintaining agitation and constant temperature (eventually drops to 52ºC when the metoxide is added) and maybe rising to a maximum of 60ºC at some instants.
I do get a clear phase separation after 24 hours, but my biodiesel isn't crystal clear.
When I mix a sample of the unwashed biodiesel with water and shake it, the emulsion won't separate…. It will after some hours, but with a lot of soap formation, widespread in the container.
I'm using good reactants (not p.a. but trustworthy) and anhydrous conditions.
There one thing I should say: I never got all the sodium hydroxide to completely dissolve in the methanol. No matter how long I keep stirring, it simply won't dissolve quantitatively. But I do filtrate the remains of solid hydroxide. Do you think this can be the problem? How can I solve it?
What can I be doing wrong? Why do I keep getting all this soap? Where do you think the problem might be? In a reactant? Bad quality oil? Do you think I should titrate the virgin oil?
Thank you all for your attention
Duarte Nuno
_______________________________________________
Biofuel mailing list
Biofuel@sustainablelists.org
http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org
Biofuel at Journey to Forever:
http://journeytoforever.org/biofuel.html
Search the combined Biofuel and Biofuels-biz list archives (50,000 messages):
http://www.mail-archive.com/biofuel@sustainablelists.org/
--
http://www.xbtz.org
http://www.rogueoperator.net
stream: http://www.xbtz.org:8000/listen.pls
stream2: http://www.xbtz.org:8002/listen.pls
24x7 streams with live shows
_______________________________________________ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org
Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
