Guidelines for care & Use of Dry Solvent Stills [Example]

At the present time, test strips for general use are kept in the small portable refrigerator kept in the
back of undergrad lab room #101. Newly purchased tubes of these test strip papers should be stored in a
refrigerator, but see the enclosed instruction sheet for storage of opened containers.
Methods for destruction of peroxides can be found in the following references:
Gordon A. J. and Ford, R. A. The Chemist’s Companion. New York: John Wiley and Sons,
1972, page 437
Perrin, D.D. and Armarego, W.L.F. Purification of Laboratory Chemicals, 3rd Edition. Oxford:
Butterworth-Heinemann Ltd., 1994.
Jackson, H.L. et al., J. Chem. Educ., 47 (1970), page A175.
When opening containers of Ethyl ether, tetrahydrofuran, or 1,4-dioxane in the solvent room #20,
which are usually purchased in large 5 gallon (or 20 liter) metal containers, please label them with the date
upon which they are first opened.
You should make an attempt to label all chemicals in your laboratory which could conceivably
form peroxides with the opening date. Please see the above mentioned table 3.13 for the list of such
chemicals.
When bottles are found to actually contain levels of peroxides above the 25 ppm concentration
range, you should not, of course, use it. You may remove the peroxides via one of the above referenced
purification methods (with your research advisor’s guidance) or carefully destroy them (again, following
specific instructions) or take them, properly labeled, to the waste holding area in room #20 for removal by
the Chemical Waste Company. Even containers with less than 25 ppm peroxide content should not be
handled or used without direct supervision from your research advisor. Obtain his/her judgment as to
whether it is best to remove the peroxides or simply have them taken out by the waste company.
GENERAL METHOD FOR DESTRUCTION OF PEROXIDES WITHIN AN ORGANIC LIQUID
Gently open the cap of the bottle and pour the organic liquid into a larger container, such as
a beaker (preferably a large 4 liter polyethylene beaker, found in the general chemistry prep room)
or a larger polyethylene pan. If the organic liquid is soluble or miscible in water, dilute it with
roughly the same volume of water. Slowly, with stirring, add a dilute solution of sodium bisulfite and
stir for about 20 minutes. Then test again for destruction of peroxides with test strips.
If the liquid is not soluble in water (such as ethyl ether) simply add a smaller volume of
aqueous sodium bisulfite to the organic liquid in a beaker and stir longer. Use a magnetic stirrer.
Again, test the organic layer for peroxides. Separate the layers in a separatory funnel and reuse the
organic liquid or bottle it up for disposal.
Washing with dilute sodium bisulfite is generally the best way to remove peroxides. You will
find sodium bisulfite in the organic chem. prep room (room #103) if you need it (see reference
Jackson, H.L. et al., J. Chem. Educ., 47 (1970), page A175).
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