JeffAMX
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A simple extraction?
Please name a extraction I can do to gain some hands on experience with chemistry. A extraction I can do without the use of a heating source that will
yield a product in maybe a crystalline form.
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Sedit
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Piperine extraction from pepper.
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
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DJF90
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How about caffeine from tea. Theres an MIT video on youtube that demonstrates it.
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DDTea
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First: read about liquid-liquid (also called acid/base) separations. Also read about recrystallization, while you're at it.
Some ideas: extract active ingredients from over the counter medicines (e.g., diphenhydramine from benadryl--I'd caution against doing an extraction
of pseudoephedrine, because that will not look good in the eyes of others).
Caffeine (really, the whole collection of adenine derivatives) from coffee/tea would be fun. Tons of plants have alkaloids in them that can be
extracted and can teach you a lot (e.g., patience). Again, though, it is illegal to extractions on many alkaloid-containing plants, so steer away
from those if you just want to learn!
"In the end the proud scientist or philosopher who cannot be bothered to make his thought accessible has no choice but to retire to the heights in
which dwell the Great Misunderstood and the Great Ignored, there to rail in Olympic superiority at the folly of mankind." - Reginald Kapp.
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turd
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??? Please explain ???
I see no reason why liquid/liquid extractions should be restricted to acids or bases, nor why A/B-extractions wouldn't work on solid/liquid systems.
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User
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http://en.wikipedia.org/wiki/Acid-base_extraction
Google is your friend 
You also do a chloroplast extraction from leaves.
What a fine day for chemistry this is.
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DDTea
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Quote: Originally posted by turd  |
??? Please explain ???
I see no reason why liquid/liquid extractions should be restricted to acids or bases, nor why A/B-extractions wouldn't work on solid/liquid systems.
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Nothing to explain, you're right. I wasn't thinking. Many acid-base extractions involve liquid-liquid extractions, so I kind of lumped the two
together in my head.
"In the end the proud scientist or philosopher who cannot be bothered to make his thought accessible has no choice but to retire to the heights in
which dwell the Great Misunderstood and the Great Ignored, there to rail in Olympic superiority at the folly of mankind." - Reginald Kapp.
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Random
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I saw on this page that solubility of piperine is 40mg/L in water. Now, piperine hydrochloride is a lot more water soluble so I was thinking about one
extraction with HCl without even using solvents.
1. Soak piperine powder in dillute HCl for few hours, maybe use warm HCl and stir the mixtue. Piperine hydrochloride is formed. Now, filter the
solution. There is solution of piperine hydrochloride and a lot more water soluble compounds.
2. Add sodium carbonate solution until the solution is basic. Now, piperine freebase precipitate is formed (solubility 40mg/L - a lot more will be
precipitated).
This should work, wouldn't it? And maybe it would even give more pure product.
[Edited on 30-3-2011 by Random]
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Nicodem
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| Quote: Originally posted by Random | | I saw on this page that solubility of piperine is 40mg/L in water. Now, piperine hydrochloride is a lot more water soluble so I was thinking about one
extraction with HCl without even using solvents. |
What is the reference for this? And please explain what do you mean by "piperine hydrochloride"? Did you even checked the structure of piperine?
| Quote: | 1. Soak piperine powder in dillute HCl for few hours, maybe use warm HCl and stir the mixtue. Piperine hydrochloride is formed. Now, filter the
solution. There is solution of piperine hydrochloride and a lot more water soluble compounds.
2. Add sodium carbonate solution until the solution is basic. Now, piperine freebase precipitate is formed (solubility 40mg/L - a lot more will be
precipitated).
This should work, wouldn't it? |
I see absolutely no reason on why it would.
In my opinion, you would do better in reading on separation techniques before doing guesswork.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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Random
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http://www.tootoo.com/d-p14985000-Piperine/
40mg/L water solubility
http://en.wikipedia.org/wiki/Piperine
"It yields salts only with strong acids."
HCl is one of the stronger acids.
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Nicodem
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There is no reference in that Wikipedia claim and the only example is the chloroplatinate 4 : 1 adduct which is not a real salt. You should be more
sceptical and check such things that make no sense (like amides forming unhydrolysable salts - most amides are only about as basic as water!).
Wikipedia is rich of such unreferenced claims which simply cannot be accounted from the literature or facts. But first of all, you always have to
check if protonation in your solvent of choice is even feasible - that's why we have pKa values to help us.
You should also not jump to wild speculations like that. Even if piperine could be hypothetically substantially protonated in water, it still does not
mean that its hydrochloride exists as a crystalline solid. It also does not mean it its hydrochloride would be water soluble. In short, protonation
does not necessarily leads to increased solubility, neither does it guarantee the existence of salts.
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GreenD
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Nicodem what is your deal - you have a tertiary amide on that ring which can undergo salt formation. Why the fuck wouldn't it?
You can extract it fine with HCl - really. WHY COULDN'T YOU?
Your giving that guy a hard time and for what?
I think a cool extraction would be (in my area atleast) taking out ginkolides and bilbolides from ginkbiloba leaves. They are easily soluble in
ethanol, and ethanol is easy to evaporate on a window sill on a hot day.
I can think of many others but they are illegal .
You said an extraction that doesn't use heat, but one of my favorites is aromatic extraction from flowers & plants, specifically a steam
distillation apparatus. All you really need is a stove, water, and some plant matter that smells nice.
A simple apparatus is EASY to set up, but hard to explain. Youtube is your friend on this one - there is a good one on extracting rose bud smells. You
need a pyrex flask, a rubber stopper, gauze, and some kind of pipe or heavy duty straw that will carry your hot liquid into a cooled jar.
This is one of the easiest seperations because when the aromatics come out they are immiscible in water, and float on top. No need for solvents or
Acid/Bases!
PS. do you guys think piperidine would be long-wave UV active?? It is certainly conjugated like a mofo.
[Edited on 31-3-2011 by GreenD]
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Nicodem
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| Quote: Originally posted by GreenD | | Nicodem what is your deal - you have a tertiary amide on that ring which can undergo salt formation. Why the fuck wouldn't it? |
Have you ever saw any experimental on how the tertiary amide hydrochlorides are prepared? Have you ever heard of any such hydrochloride being stable
to water or moisture? Have you even bothered checking the pKa values of amides before posting?
| Quote: | | You can extract it fine with HCl - really. WHY COULDN'T YOU? |
The question was WHY COULD YOU? And you did not answer that, despite claiming something that goes against general chemical knowledge. At least I
answered why you COULD NOT and for that I get accused of giving someone a hard time. Well, you know what, learning is all about having a hard time.
Well, if you don't trust me, try trusting the literature and see the page 55 of Allen's commercial organic analysis, most likely the only mention of "piperine hydrochloride" ever:
| Quote: | Piperine is a feeble base. Its salts are decomposed by excess of water with precipitation of free piperine, and the alkaloid is extracted even from
its acidified solutions by agitation with chloroform, benzene, petroleum spirit, etc. Piperine hydrochloride is soluble in alcohol, and on
treating the solution with alcoholic mercuric chloride or platinic chloride the corresponding compounds are obtained as crystalline precipitates. 1
1 The composition of these salts is said to be respectively (C17H19O3N)2, HCl, HgCl2, and (C17H19O3N)4. 2HCl, PtCl4. |
And it gives no reference for the characterization data on "piperine hydrochloride", so this could be nothing else but the ethanolic solution of
piperine and HCl.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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