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Peroxide Forming Chemicals
CONTENTS
Introduction
Neutralisation of peroxides
Tables
Table 1: Organic Functional Groups Prone to Peroxide Formation
Table 2: Inorganic Substances Prone to Peroxide Formation
Table 3: Common Peroxide Forming Chemicals and Recommendation For Their
Testing and Disposal
References
Introduction
There are many organic functional groups and inorganic substances that are susceptible to
peroxide formation. These are shown in Table 1 and Table 2, respectively.
Examples of specific chemicals that undergo peroxide formation are listed in Table 3, along
with recommendations for the testing of peroxides in, and / or the disposal of, the peroxide
forming chemicals which are listed.
Tables
No.
Functional
Group
Description
- hydrogen atoms
1
|
H-C-O-R
|
\
|
C=C-C-H
/
|
Alkenes with allylic hydrogen atoms
2
\ |
C=C-X
/
Chloro- and fluoro- alkenes
3
\
C=CH2
/
Vinyl halides, esters and ethers
4
\ | |
/
C=C-C=C
/
\
Dienes
5
\
C=C(H)-C≡C-H
/
- hydrogen atoms
6
|
H-C-C≡C-H
|
- hydrogen atoms
7
8
|
H-C-Ar
|
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Alkyl
aromatics
hydrogen atoms
containing
tertiary
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9
|
H-C-R
|
Alkanes and cycloalkanes
tertiary hydrogen atoms
containing
\
C=C-C(O)OR
/
Acrylactes and methacrylates
10
|
H-C-OH
|
Secondary alcohols
11
12
\
H-C-C(O)/
|
H-C=O
Aldehydes
13
14
\
|
H-C-N(H)-C=O
/
Amides, ureas and lactams that have an ahydrogen atom on a carbon attached to a
nitrogen
- hydrogen atoms
Where: R is an alkyl group
X is a chlorine or fluorine atom; and
Ar is an aromatic group.
Table 1: Organic Functional Groups That Are Prone To Form Peroxides
(Listed in decreasing order of approximate likelihood of peroxide formation)
Type
Examples
Alkali metals
Potassium, Rubidium, Caesium
Metal amides
Sodium amide, Potasium amide
Organometallics
n-Butyllithium, Phenyllithium, Phenylsodium
Metal alkoxides
Aluminium n-butoxide, Iron (III) ethoxide
Table 2: Inorganic Substances That Are Prone To Form Peroxides
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Severe Peroxide Hazard
a
Discard within 3 months
 Diisopropyl
ether
(isopropyl ether)
 Divinylacetylene
(DVA)
 Potassium metal
 Potassium amide
 Sodium
amide
(sodamide)
 Vinylidene
chloride
(1,1-dichloroethylene)
[a]
[b]
[c]
[d]
Peroxide Hazard On
Concentration b
Discard or test for peroxides
after 6 months
 Acetaldehyde diethyl acetal
 Cumene
 Cyclohexene
 Cyclopentene
 Decalin
 Diacetylene (1,3-butadiyne)
 Dicyclopentadiene
 Diethyl ether
 Diethylene glycol dimethyl
ether
 Dioxane
 Ethylene glycol dimethyl
ether
 Ethylene glycol ether
acetates
 Ethylene glycol monoethers
 Furan
 Methylacetylene
 Methylcyclopentane
 Methyl isobutyl ketone
 Tetrahydrofuran (THF)
 Tettralin
 Vinyl ethers
Potential For Rapid
Polymerisation c
Discard or test for peroxides
after 6 months
 Chloroprene (2-chloro-1,3butadiene) d
 Styrene
 Vinyl acetate
 Vinyl pyridine


Discard after 12 months
Butadiene d
Tetrafluoroethylene (TFE)
d


Vinylacetylene (MVA) d
Vinyl chloride
On storage with exposure to air
Do not distil or evaporate without first testing for the presence of peroxides
Due to Internally Formed Peroxides
When stored in liquid phase without an inhibitor, these should be considered to pose a
severe peroxide hazard, and be discarded within 3 months of exposure to air.
Table 3: Common Peroxide Forming Chemicals
Removal of peroxides
If a precipitate or crystals are present in a peroxide-forming chemical do not open the
lid. Secure and label the area around the chemical so that it is protected from
movement and can’t be disturbed. The chemical should be disposed of in a safe
manner by a specialised waste contractor, or the local budget unit’s Hazardous Waste
Safety Officer or the Work Environment Group contacted for advice on the treatment of
the chemical.
Peroxides may be removed using one of the two methods below:
Method 1
Pass the solvent through a short column of activated alumina. (A suggested amount is 100g
of alumina per 100mL of solvent). Retest the solvent to ensure that peroxides have been
removed. Some peroxide may be retained on the column, which should then be disposed of
as a flammable material. Solvents purified in this way should be used directly and not stored
further as any peroxide-forming inhibitor will probably have been removed (see Standard
Laboratory Practises Document for testing).
Method 2
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Shake gently the solvent with a freshly prepared solution of iron (II) sulphate (60g iron (II)
sulphate, 6mL concentrated sulphuric acid and 110mL water per litre of ether). Repeat until
peroxides are no longer detected after testing (see Standard Laboratory Practises Document
for testing). Shake very gently for the first extraction. Be careful of rise in temperature and
build up of pressure.
References
1. National Research Council, Prudent Practices in the Laboratory: Handling and
Disposal of Chemicals, National Academy Press, Washington D.C. (1995).
2. Bretherick, L., Bretherick’s Handbook of Reactive Chemical Hazards, 4th Edition,
London: Butterworth. (1990).
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