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Author: Subject: Nepetalactone extraction
Quince
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[*] posted on 16-2-2006 at 22:56
Nepetalactone extraction


I attempted to extract the essential oil from catnip in a Gregar extractor using ethanol as the solvent. Unfortunately, the high boiling temperature of the ethanol resulted in some burning along the boiling flask.

Some questions:
The most common solvent for extracting essential oils from aromatic plants seems to be hexane. However, I don't see where I can obtain this OTC. Any appropriate substitutes? One I've seen mentioned occasionally is methylene chloride.
Another thing is, how do I separate out various things the solvent took along from the oil? The ethanol extracted most of the chlorophyll. And hexane extracts a lot of waxy substances besides oils.




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leu
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[*] posted on 17-2-2006 at 04:31


Chromatography is the normally used technique for such separations :D



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[*] posted on 17-2-2006 at 16:33


you would normally extract with some solvent (hexane or whatever) then distill off the solvent to obtain the residual gum and fractionally distill this under hard vacuum to obtain whatever fraction you want.

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[*] posted on 17-2-2006 at 17:30


"White gas" or "White spirit" , as used in liquid fuelled camp stoves, is mostly n-Hexane.



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Quince
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[*] posted on 17-2-2006 at 19:15


Twospoons, white gas/spirit, according to the Web, is a mixture of a whole bunch of stuff, and only some limited percentage is hexane. With my luck, it probably forms azeotropes with some of the other ingredients.

[Edited on 18-2-2006 by Quince]




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[*] posted on 19-2-2006 at 14:56


Obviously some posters are taught differently than others have been. Attempting to reinvent the wheel is rather inefficient, library research is often more productive in finding the already published procedure :cool: This problem was solved at the University of Wisconsin many years ago, the paper on the isolation of nepetalic acid, nepelactone and related compounds has been uploaded to the Wet Dreams thread for literature requests from this and other forums :D

[Edited on 19-2-2006 by leu]




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[*] posted on 19-2-2006 at 20:16


I'm unable to access the site.
Why do you have to be so difficult and not at least post the citation, so I can at least find the paper myself?




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[*] posted on 20-2-2006 at 00:03


In the attached 2005 paper, under traditional method (procedure B in the experimental section), they extract with methylene chloride the water from the mincing, and the solid stuff, separately. Why???

Also, where do I get the silica for method A? It's not clear to me from the description exactly how to perform this method. Anyone care to propose a DIY method?

Attachment: np049647d.pdf (132kB)
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