kazaa81 - 29-10-2005 at 11:07
Hallo to all,
I've read that limonene (a terpene) can be made by "dry distillation" of gum (caucciù, pneumatics), an old process of
distillation...if is possible i'd want to try this.
http://en.wikipedia.org/wiki/Limonene
Thanks all for help
Marvin - 29-10-2005 at 13:19
I'm not convinced that is a good method, its not one Ive heard of. Assuming it does work I think it would depend to a very large extent on the
type of gum you used. I'd avoid this.
Depending on which enantiomer you want, you can try steam distillation of orange or lemon peel. Ive done this, I remeber getting 1ml or so from the
peel of a few oranges.
Terpenes
kazaa81 - 30-10-2005 at 07:37
Thank you Marvin, but I probably haven't sufficient equipment to do a steam flow distillation...if getting lemon peels boiled in water and all
what boils away get collected, then I can try this.
I was thinking...distilling camphor (C10H16O) with a dehydrating agent (ex. ZnCl2, phosphoric anhydride) yield cymol (C10H14).
C10H16O - H2O ---> C10H14
Limonene is C10H16, so can it be obtained from Camphor, who is C10H16O?
Can be CaCl2 a suitable dehydrating agent to convert camphor to cymol (cymene)?
Thanks all for help!
neutrino - 30-10-2005 at 13:44
You want to make
into
by dehydration with a salt? Sorry, it's not that simple.
kazaa81 - 31-10-2005 at 13:02
From "King's American Dispensatory"
(http://www.ibiblio.org/herbmed/eclectic/kings/cinnamomum-cam...)
"Japan camphor may be converted into cymol by distillation with zinc chloride, or with phosphoric anhydride, which agencies abstract from camphor
the elements of water, thus: C10H16O-H2O=C10H14."
Now, I haven't tried because don't have Zn salts...
Any information welcomed
neutrino - 31-10-2005 at 15:03
It appears we are talking about completely different camphors. King's 'Japan Camphor' is a monocycle, ordinary household camphor is a
bicycle.
kazaa81 - 31-10-2005 at 16:14
I want to try this....with synthetic camphor and CaCl2.
Anything interesting that can be done with camphor?
Any other limonene info/synthesis?
Any info. welcomed!
Marvin - 1-11-2005 at 08:18
I do not see a problem with the basic idea, the camphors are not different. I have no idea what the yeild would be though.
ZnCl2 is a dehydrating agent and also a good lewis acid. I would expect CaCl2 to fail miserably. CaCl2 is not a lewis acid, and gives up its water
on heating it may as well be not there.
kazaa81 - 2-11-2005 at 12:47
Lewis acids, how could I have forgotten this?
I've tried to boil camphor with conc. H2SO4 and collect the distillate, but I got a black, nasty odour mass, which has dirt my glassware....
kazaa81 - 4-11-2005 at 13:27
Another suitable lewis acids is AlCl3...
Anyone have experience on this?
ordenblitz - 4-11-2005 at 15:53
A couple of things you can do with Limonene
(-)-Menthol Synthesis from (+)-Limonene
http://www.leffingwell.com/menthol7/menthol7.htm
or this....
http://www.chem.gla.ac.uk/staff/amalkov/Synthetic%20applicat...
kazaa81 - 5-11-2005 at 12:48
Thank you!
But first I need to synthetize/extract limonene!!!
Any info. about limonene welcomed! 
[Edited on 6-11-2005 by kazaa81]
kazaa81 - 6-11-2005 at 06:49
http://www.nicnas.gov.au/PUBLICATIONS/Information_Sheets/Saf...
Limonene MSDS
kazaa81 - 19-11-2005 at 13:23
I've tried some other with cymol from camphor but probably something has gone wrong...
Any info. welcomed!
mick - 24-11-2005 at 12:26
Extraction of limonene from orange peel.
2-3 oranges depending on their size.
Use a potato peeler or some thing to take off the orange layer, you do not want the soft white layer (plastic handled peelers start softening after
peeling a few oranges).
Chop finely or liquidize with 150 ml water briefly.
Dont puree otherwise you end up with and emulsion and the stuff just burns and cracks the flask during the distillation.
Make up to 350-400 ml with water and distil.
Try and shake the distillation flask a bit otherwise the orange residue starts charring.
Distil 100 ml or until the distillate is clear, if necessary add more water.
Usually an ether extraction and evaporation of the distillate will give you the limonene, as Marvin said about a ml.
Without the ether, ethyl acetate or some similar organic solvent might work or it might be possible to salt the limonene out and dry it with MgSO4 or
Na2SO4.
I think the purification is from the steam distillation and not the extraction.
mick