Page 253 - Demo

“Your Safer Source for Science”
Flinn Method #14, continued 2
Chemical Disposal Procedures
251
Fill a large beaker 1⁄2 full of water, and using pH paper, make it basic (at least pH 12) by adding 3 M sodium hydroxide solution, as needed.
3
3MNaOH
#18a Water-SolubleAlcohols,Ketones,Esters
Low-molecular weight, oxygen-containing organic compounds are volatile, soluble in water, and biodegradable. Aqueous solutions and extracts containing less than 24% of volatile alcohols, ketones, and esters—see the examples below—may be disposed in small quantities down the drain (sanitary sewer only) with excess water. Please check all federal, state, and local regulations that may apply before proceed- ing. See Flinn Suggested Disposal Method #26b for more information on drain disposal.
Examples
Acetone, isopropyl alcohol, ethyl acetate
#18b HydrocarbonsandFlammable Ketones, Esters, Alcohols
Nonvolatile organic compounds do not readily evaporate and are not easily converted into less toxic materials. The only disposal procedures available are disposal by a licensed hazardous waste company.
FLINN METHOD
pH Paper
FLINN METHOD
Dissolve the iron cyano-complex in the water.
4
While stirring,
slowly add the
sodium hypochlo-
rite solution (about
100 mL per g CN)
or 30% calcium
hypochlorite solu-
tion (20 mL per g CN). Heat may be evolved; maintain the temperature below 50 °C by using an ice bath if necessary. Once the addition of hypochlorite is completed (use a twofold molar excess), allow the mixture to stand for several hours.
5
Rinse the mixture down the drain with a 20-fold excess of water.
FLINN METHOD
30% Ca(OCI)2 Ice and Water
#20 Organic Amides
Check the Safety Data Sheet (SDS) to determine whether the organic amide will be a characteristic ignitable waste (flash point <60 oC) or if it is a listed waste. Organic amides that are not hazardous wastes may be packaged for landfill disposal according to Flinn Suggested Disposal Method 26a. Characteristic and listed hazardous wastes require licensed hazardous waste disposal (see Flinn Suggested Disposal Method 26c.)
#22a Peroxides,Inorganic
Inorganic peroxides are strong oxidizing agents and are classified by the EPA as ignitable characteristic wastes. Leftover inorganic perox- ides may be reduced as part of an experimental procedure. When in contact or mixed with organic or combustible materials, fires or explo- sions are possible. Do not discard these materials in the trash!
Examples
Hydrogen peroxide, sodium peroxide
Materials Required
Large beaker, 3⁄4 full of water Plastic spoon (optional) Plastic stirring rod
pH paper
Sodium metabisulfite, Na2S2O5, 1 M Hydrochloric acid, HCl, 3 M
Overview
Hydrogen peroxide may be reduced with sodium metabisulfite to render it suitable for drain disposal.
Sodium peroxide reacts violently with water to form oxygen gas and sodium hydroxide. Because of this reaction, sodium peroxide is stored in sealed containers to avoid reaction with moisture in the air. With fresh sodium peroxide the reaction with water is quite exothermic, but if used from a previously opened container, it may be less vigor- ous. Old sodium peroxide may have already slowly converted itself to sodium hydroxide. Test the materials for reactivity by adding a small amount (0.1 g) to water. Evolution of oxygen indicates an active perox- ide. Leftover or excess sodium peroxide may be reduced.
Na2O2 + H2O → 2NaOH + 1⁄2O2 Na2O2 + Na2S2O5 + H2O → 2NaOH + NaHSO4
FLINN METHOD
FLINN METHOD
#15 Ethers
Bottles of ethers that have been opened and are more than a year old may contain hazardous quantities of explosive peroxides. These bottles will require licensed hazardous waste disposal. Some companies will require that the peroxide level be verified before accepting ethers for disposal.
#16 Hydrazines and Their Salts
Hydrazines contain a nitrogen–nitrogen single bond and are very reac- tive. Many hydrazines are also toxic and/or carcinogenic. Hydrazines should be disposed of by a licensed hazardous waste disposal company according to Flinn Disposal Method #26c.
FLINN METHOD
Please...Read the Narratives
Important narratives precede these specific chemical disposal methods! Please read each narrative carefully! Do not use these procedures if you are not comfortable with the chemistry. Do not use these procedures without first consulting with your local government regulatory officials. These procedures may not be used in some jurisdictions. All procedures involve some hazards and risks. Once again...read the narratives that precede these specific chemical disposal methods.
FLINN METHOD #22a continued on next page.