I have not tried this procedure and I would be curious to know how
well it
works.
I do not know the scale at which the class at your university
performs this
experiment, macroscale, small scale, semi-micro, or micro. That
will also
affect the extraction solvent used. For semi-micro scale or
microscale
procedures, I agree with Ernie Lippert that students must learn how to
work with
chemicals such as dichloromethane safely. That includes the
generation of only small quantities of waste product.
In another experiment, I have my class extracting the fat from
potato chips
and French fries. Starting with 5 g of chips or 10 g of French
fries in a
125-mL flask, I have switched the solvent from dichloromethane to hexane
and
use several rinsings of 10 mL or less. The solvent is
disposed of in
a waste bottle and the chips or fries which are only slightly damp with
solvent,
in the flask, are dried in a water bath under the hood. The
fat
content is determined by the loss in mass. We get good
results.
David
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David A.
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and
Consultant
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