devongrrl
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Transesterification of Castor Oil
I've just been reading a paper called "TRANS ESTERIFICATION STUDIES ON CASTOR OIL AS A FIRST STEP TOWARDS ITS USE IN BIO DIESEL PRODUCTION"
Pak. J. Bot., 40(3): 1153-1157, 2008.
The paper suggests using KOH as a catalyst in the esterification of castor oil with methanol to yield Methyl Ricinoleate.
I'm wondering whether NaOH could be substituted as the catalyst ?
Anyone interested in the paper can find in at
| Code: | www.pakbs.org/pjbot/PDFs/40(3)/PJB40(3)1153.pdf |
[Edited on 19-8-2010 by devongrrl]
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Eclectic
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Yes, I've done the reaction with ethanol and NaOH.
Good clean separation of ethyl ricinoleate from alkaline glycerine layer at bottom.
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Fulmen
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It's an old thread, but the only one I could find on ethyl ricinoleate. I assume one can make the ethyl ester with the same procedure and molar
amounts, but will it have similar plasticizing properties in conjunction with say PIB?
We're not banging rocks together here. We know how to put a man back together.
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Magpie
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What's PIB?
The single most important condition for a successful synthesis is good mixing - Nicodem
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Metacelsus
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Polyisobutylene.
–(–CH2–C(CH3)2–)n–
[Edited on 12-9-2015 by Cheddite Cheese]
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Fulmen
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Sorry, I could have provided more detail. Yes it it polyisobutylene, and it's for making plastic binder for energetic materials. While methanol is
available it's not as easy to get as 96% ethanol, and I prefer to use easily obtainable chemicals as long as it's possible.
We're not banging rocks together here. We know how to put a man back together.
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Dr.Bob
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But using 96% ethanol will give a poor yield compared to using 100% methanol for a transesterification. That is why almost no one makes biodiesel
with ethanol, it is more than an order of magnitude harder to get to work, as water is bad, ethanol is sterically more hindered than methanol, and
ethanol has a higher MW, requiring even more ethanol by weight/volume than methanol, which limits the excess amount of ethanol possible. While NaOH
and KOH are somewhat interchangable for that reaction, methanol and ethanol are not easily swapped. It might be easier to get dry/pure NaOH, which
is helpful.
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diddi
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I have done with other (canola, palm) oils. MeOh better than EtOH as Dr Bob says, in my experience.
Beginning construction of periodic table display
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XeonTheMGPony
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Methanol is a very common substance in Auto motive suplies used for fuel line antifreeze and to dewater tanks (It allows the water to be carried with
the fuel to be burned off)
For sources of pure methanol hydrate look to auto shops, and paint shops.
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