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

Concentrated solution of Dodycylbenzene sulphonic acid and potassium hydroxide(“Contrad-70”): This
serves as a biodegradable, drain disposable alternative to chromerge. It is sold by Fisher Scientific Co.,
Catalog # 04-3551. Prepare a 5% solution from the concentrate for lab use.
“Dilute Nitric Acid Cleaning Solution: Films which adhere to the inside of flasks and
bottles may often be removed by wetting the surface with dilute nitric acid, followed
by multiple rinses with distilled water. Concentrated Nitric acid is good for tougher
organic chemical stains.” Use in a hood only.
“Aqua Regia Cleaning Solution: Aqua regia is made up of three parts of concentrated
HCl and one part of concentrated HNO3. This is a very powerful, but extremely
dangerous and corrosive, cleaning solution. Use in a hood with extreme care.”
“Alcoholic Potassium Hydroxide or Sodium Hydroxide Cleaning Solution: Add
about 1L ethanol (95%) to 120ml H20 containing 120g NaOH or 105g KOH. This is
a very good cleaning solution. Avoid prolonged contact with ground-glass joints on
interjoint glassware because the solution will etch glassware and damage will result.
This solution is excellent for removing carbonaceous materials.”
(Ballinger, Jack T. and Shugar, Gershon J. Chemical Technicians’ Ready Reference
Handbook, 3rd edition. New York City: McGraw-Hill, Inc., 1990, pages 611-612).
8. Broken Glassware Procedure: Waste containers stenciled with the label “Broken Glassware Only”
have been placed in each laboratory. Broken glass should be placed in these containers, only, and only
glass should be placed there. Glassware broken in the course of experimental work should be rinsed of
chemical contaminants, preferably with acetone, and the rinses deposited in lab chemical waste containers.
Shards of broken glass found in common departmental waste containers are dangerous for housekeeping
staff to handle. Glass should not therefore be mixed with paper and other common forms of trash. Make
sure that the top surface of broken glass within the Broken Glassware box does not overflow, resulting in
dangerous situations for Housekeeping staff handling these boxes. It is requested that all research students
and Teaching assistants within the undergraduate teaching labs occasionally check these boxes for overly
jagged pieces of glass protruding through the side of the cardboard box or tearing up the plastic bag liner
inside the box.
9. Needles used for transferring chemical samples from one container to another or injection into
instruments should be disposed of into red plastic containers marked “For Disposal of Non-reusable
Needles, Only” placed in each research Lab requiring them. These containers will be collected when 80%
full, stored in a large marked box in the Solvent Room # 20, and given to a biological Sharps (Needles, etc.)
waste disposal company, such “Steri Cycle” Company, even though the Chemistry Department does not
employ such needles in animal or human experiments. Replacement containers are located in room 20 or
can be purchased from Fisher Scientific, catalog # 14-827-122 Needles which are meant to be reused
should not be kept on counter tops without some provision to prevent accidental “sticking”. You can cap
them, place them in holding packages or lab drawers, or request plastic holding containers from the
department and gather them all into one holding container.
Please do not overfill the Non-Reusable needle containers. Instead, leave 2 inches of "headspace"
in each container at the top. Insofar as possible, do not place anything in these containers other than
needles and the plastic sheathing associated with the needle. Large plastic and glass syringe tubes should be
rinsed and disposed of in the garbage (glass syringe tubes go in with the broken glass boxes, of course). If
you have the least bit of difficulty in removing smaller syringe tubes from the needle, then by all means
drop the entire needle/tube assembly into the container for disposal.
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