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Topic: another question - ethanol , hot or cold?  (Read 6197 times)

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mordoh

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another question - ethanol , hot or cold?
« on: June 21, 2004, 08:07:56 AM »
hey ,

i wanted to know, can i do extraction of plant/herb with 70% ethanol (hot) for 3-4 hours and it will be exactly the same to extraction with cold ethanol for 2 weeks?

if not , whats the diffrence?

thanks

Offline Mitch

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Re:another question - ethanol , hot or cold?
« Reply #1 on: June 22, 2004, 06:19:06 PM »
The difference is solubillity. Solubility is a function of temperature. Typically the higher the temperature the more soluable a substance is in that medium.
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Doxorubicin

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Re:another question - ethanol , hot or cold?
« Reply #2 on: June 30, 2004, 11:30:19 PM »
It depends on what you are extracting.  

cfthb

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Re:another question - ethanol , hot or cold?
« Reply #3 on: July 14, 2004, 04:58:42 PM »
Assuming that the cold extraction is also done with 70% EtOH, the quantity of solute that will dissolve should be the same, regardless of temperature; it's just much faster to do it with the hot solvent.  The nature of the solute won't matter.  BUT - the difference in solubility btwn hot/cold solvents is huge, and two weeks cold may not approach what you can do at reflux for several hrs.

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