flinnsci.com SAFETY REFERENCE CHEMICAL DISPOSAL PROCEDURES
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16 Steps to Minimize Chemical Disposal
Smart, Inexpensive Practices to Reduce Hazardous Waste
The single largest chemical problem facing most
academic institutions today is chemical disposal.
Purchasing chemicals in large package sizes, poor
chemical inventory management, faculty and staff
turnover and changes in the curriculum are just a
few of the many reasons why your school may have a
chemical disposal problem. Every school, college and
university needs a plan to minimize future laboratory
chemical/disposal issues. Chemical disposal is a
necessary part of any chemical laboratory activity.
The following 16 steps will help reduce the amount
of chemicals that need to be disposed and make the
disposal process easier to manage.
1. Maintain an up-to-date inventory of your
chemicals.
Maintaining a good chemical inventory will
eliminate buying excess or unneeded chemicals.
2. Purchase chemicals carefully.
Care ful purchasing is the first step in decreasing
the amount of unwanted chemicals and
subsequent chemical disposal. To reduce
unwanted chemicals, purchase smaller size
packages of chemicals, only what is needed for
the next 1 to 3 years and only from chemical
suppliers that will guarantee fresh chemicals. If
you only need a dilute solution of a chemical, buy
the solution and not a large bottle of the solid.
Buying chemicals in bulk to save a few dollars
ends up costing more in the long term. Disposal of
unused chemicals always will cost more than any
cost savings from larger sized packages.
3. Date label your chemicals, and only buy from
chemical supply companies that date label
their chemicals.
Chemicals age at different rates, and knowing the
age of your chemicals may help you determine if
they are still usable.
4. Use older chemicals first before they
decompose.
This requires date labeling of chemicals.
5. Provide good climate control for the chemical
storeroom.
Store chemicals in a cool, dry environment. Heat
and humidity quickly degrade chemicals, resulting
in materials that are unsuitable for laboratory use
and require disposal. This is particularly important
during the summer months when many schools
may turn off their air conditioning.
6. Ventilate your storeroom.
Provid ing a continuous air exchange in your
storeroom is not only safer for you, but it will
provide a better environment for storage of
chemicals.
7. Label all chemicals and laboratory solutions.
Any unlabeled bottle becomes a chemical
disposal nightmare; first the chemical must be
identified, then it must be discarded properly. To
avoid unknown and unwanted solutions, replace
or repair old labels and immediately label all
prepared solutions.
8. Prepare only enough solution for immediate
use.
Preparing extra solution for storage frequently
results in many bottles of unwanted solutions that
ultimately require disposal.
Be proactive… Reduce chemical
waste starting today.
9. Never store chemicals or solutions in
“homemade” bottles.
Stor ing solutions in containers not designed for
chemical storage leads to a shorter shelf life of the
laboratory chemical. “Home made” bottles may not
provide suitable protection from the environment
or may not be compatible with the chemical. Using
proper chemical containers will provide safer
storage and allow for longer storage of chemical
solutions.
10. Store hygroscopic and deliquescent chemicals
in Chem-Saf™ bags.
Make sure the caps are on tight and use Parafilm
M® around the cap for extra protection. Chem-Saf™
bags and tight caps help keep moisture out of
containers and greatly increases their shelf life.
11. Follow good laboratory practices.
Never allow students to place chemicals back into
a chemical reagent bottle. Contamination from
student use will dramatically reduce purity and
the shelf life of a chemical. To enforce this practice,
place smaller amounts of chemicals in beakers or
bottles for dispensing.
12. Microscale your labs.
Microscale laboratory procedures can reduce your
wastes a hundredfold. Many times the quantities
produced in a microscale lab can be disposed of
down the drain. If you microscale your labs, also
microscale the quantity of chemicals you purchase
(see step 2).
13. Purchase chemical demonstration kits or
student laboratory kits that contain the exact
quantities of chemicals.
This eliminates storage and disposal of “extra”
chemicals. Flinn chemical demon stration
kits contain enough chemicals to present the
demonstration seven times. At the end of the day,
there are no unused or unwanted chemicals.
14. Look at disposal procedures first.
When choosing a lab or demonstration, look at the
disposal procedure first. If the disposal procedure
is difficult, consider using microscale techniques
or substituting less hazardous materials. Avoid the
use of heavy metals whenever possible.
15. Neutralize, reduce byproducts and dispose
of chemicals immediately after they are
generated.
Do not stockpile unwanted byproducts or other
laboratory wastes from chemical reactions or
experiments. Treat chemical byproducts or leftover
solutions as part of the experimental procedure.
This is safer and easier than stockpiling chemicals
for a massive disposal at the end of the year.
16. Identify hazardous waste, and keep waste
solutions separate.
Never mix leftover chemicals or byproducts from
different labs unless the materials have identical
dis posal methods and are chemically compatible.
Adding a small amount of a lead compound to
a waste bottle necessitates licensed hazardous
waste disposal of the entire contents due to heavy
metal contamination.
Implementing and following these 16 steps to
minimize chemical waste will save money and
improve the overall safety profile of your school.
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