Difference between revisions of "Peroxide forming chemicals"

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===Disposal===
 
===Disposal===
Sensitive peroxides can be neutralized using a reducing agent, like [[sodium sulfite]] or [[Iron(II) sulfate|ferrous sulfate]].
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Sensitive peroxides can be neutralized using a reducing agent, like [[sodium sulfite]] or [[Iron(II) sulfate|ferrous sulfate]]. For ethers, metallic sodium can also be used, along with stirring or refluxing for better performance.
  
 
DO NOT ATTEMPT TO OPEN VERY OLD BOTTLES THAT HAVE PEROXIDES ON THE CAP!
 
DO NOT ATTEMPT TO OPEN VERY OLD BOTTLES THAT HAVE PEROXIDES ON THE CAP!

Revision as of 11:36, 7 September 2019

Peroxide forming chemicals are a group of chemical compounds capable of forming very sensitive peroxides if exposed to atmospheric oxygen. While most are organic, potassium metal is known to form the unstable potassium peroxide (K2O2) in contact with air.

Chemicals that form peroxides when treated with hydrogen peroxide or some other form of peroxide are not included in this group, as these compounds require an already existing peroxide and do not form such peroxides in contact with atmospheric oxygen. Like wise, chemicals that form peroxides at high temperatures (like barium oxide) or other extreme/unique conditions are also not included here.

General

Chemical compounds, such as ethers, secondary alcohols or certain unsaturated hydrocarbons will produce unstable peroxides upon contact with air, process accelerated by light or heat, over the course of months or years. The autoxidation of said compounds produces both normal peroxides, as well as hydroperoxides.[1][2] There are 2 main categories of peroxide forming chemicals, as well as two additional more.[3][4]

Ethers like dimethyl ether, methyl tert-butyl ether and tertiary ethers do not form explosive peroxides in contact with air, due to the lack of α hydrogens.

Categories

Group A

Compounds that form explosive levels of peroxides without concentration, and can explode without warning at high enough concentrations.

Group B

Compounds that form explosive levels of peroxides during concentration, and tend to explode when dry. Safe when wet.

Group C

Compounds which are hazardous due to peroxide initiation of autopolymerization.

  • Acrylic acid
  • Acrylonitrile
  • Butadienea
  • Chlorobutadiene
  • Chloroprenea
  • Chlorotrifluoroethylene
  • Methyl methacrylateb
  • Styrene
  • Tetrafluoroethylene
  • Vinyl acetate
  • Vinyl acetylene
  • Vinyl chloride
  • Vinyl pyridine
  • Vinyldiene chloride

Group D

Chemicals that may form peroxides but cannot be classified in the previous categories

  • 1-Ethoxy-2-propyne
  • 1-Ethoxynaphthalene
  • 1-Octene
  • 1-Pentene
  • 1-(2-Chloroethoxy)-2-phenoxyethane
  • 1-(2-Ethoxyethoxy)-ethyl acetate
  • 1,1-Dimethoxyethane
  • 1,1,2,3-Tetrachloro-1,3-butadiene
  • 1,2-Bis(2-chloroethoxy)-ethane
  • 1,2-Dibenzyloxyethane
  • 1,2-Dichloroethyl ethyl ether
  • 1,2-Diethoxyethane
  • 1,2-Epoxy-3-isopropoxypropane
  • 1,2-Epoxy-3-phenoxypropane
  • 1,3-Butadiyne
  • 1,3-Dioxepane
  • 1,3,3-Trimethoxy-propene
  • 1,5-p-Methadiene
  • 2-Bromomethyl ethyl ether
  • 2-Chlorobutadiene
  • 2-Ethoxyethyl acetate
  • (2-Ethoxyethyl)-o-benzoyl benzoate
  • 2-Ethylbutanol
  • 2-Ethylhexanal
  • 2-Methoxy-ethanol
  • 2-Methyltetra-hydrofuran
  • 2,2-Diethoxypropane
  • 2,4-Dichlorophenetole
  • 2,4-Dinitrophenetole
  • 2,4,5-Tri-chlorophenoxyacetate
  • 2,5-Hexadiyn-1-ol
  • 3-Bromopropyl phenyl ether
  • 3-Ethoxyopropionitrile
  • 2-Ethylacrylaldehyde oxime
  • 3-Methoxy-1-butyl acetate
  • 3,3-Dimethoxypropene
  • 4-Methyl-2-pentanone
  • 4-Vinyl cyclohexene
  • 4,5-Hexadien-2-yn-1-ol
  • Acrolein
  • Allyl ether
  • Allyl ethyl ether
  • Allyl phenyl ether
  • Benzyl 1-napthyl ether
  • Benzyl ether
  • Benzyl ethyl ether
  • Benzyl methyl ether
  • Benzyl n-butyl ether
  • Bis(2-chloroethyl) ether
  • Bis(2-ethoxyethyl) adipate
  • Bis(2-ethoxyethyl) ether
  • Bis(2-ethoxyethyl) phthalate
  • Bis(2-(methoxyethoxy)-ethyl) ether
  • Bis(2-methoxyethyl) carbonate
  • Bis(2-methoxyethyl) ether
  • Bis(2-methoxyethyl) phthalate
  • Bis(2-methoxymethyl) adipate
  • Bis(2-n-butoxyethyl) phthalate
  • Bis(2-phenoxyethyl) ether
  • Bis(4-chlorobutyl) ether
  • Bis(chloromethyl) ether
  • Buten-3-yne
  • Chloroacetaldehyde diethylacetal
  • Chloroethylene
  • Chloromethyl methyl ether
  • Cyclooctene
  • Cyclopropyl methyl ether
  • Di(1-propynyl)ether
  • Di(2-propynyl)ether
  • Di-n-propoxymethane
  • Diallyl ether
  • Diethoxymethane
  • Diethyl acetal
  • Diethyl ethoxymethylene-malonate
  • Diethyl fumarate
  • Diethyketene
  • Dimethoxymethane
  • Dimethylketene
  • Ethyl vinyl ether
  • Ethyl β-ethoxy-propionate
  • Furan
  • Isoamyl benzyl ether
  • Isoamyl ether
  • Isobutyl vinyl ether
  • Isophorone
  • Limonene
  • m,o,p-Diethoxybenzene
  • m-Nitro-phenetole
  • Methonxy-1,3,5,7-cyclooctatetraene
  • Methyl p-(n-amyloxy)benzoate
  • n-Amyl ether
  • n-Butyl phenyl ether
  • n-Butyl vinyl ether
  • n-Hexyl ether
  • n-Methylphenetole
  • n-Propyl ether
  • n-Propyl isopropyl ether
  • o-Bromophenetole
  • o-Chlorophenetol
  • o,p-Ethoxyphenyl isocyanate
  • o,p-Iodophenetole
  • Oxybis(2-ethyl acetate)
  • Oxybis(2-ethyl benzoate)
  • p-(n-Amyloxy)benzoyl chloride
  • p-Bromophenetole
  • p-Chlorophenetole
  • p-Di-n-butoxybenzene
  • p-Dibenzyloxybenzene
  • p-Ethoxyacetho-phenone
  • p-Phenylphenetone
  • Phenoxyacetyl chloride
  • Phenyl o-propyl ether
  • Sodium 8,11,14-eicosa-tetraenoate
  • Sodium ethoxyacetylide
  • tert-Butyl ethyl ether
  • Tetrahydropyran
  • Triethylene glycol diacetate
  • Triethylene glycol dipropionate
  • Vinylene carbonate
  • Vinylidene chloride
  • α-Phenoxy-propionyl chloride
  • β-Bromophenetole
  • β-Chlorophenetole
  • β-Isopropoxy-propionitrile
  • β-Methoxy-propionitrile
  • β,β-Oxydi-propionitrile

Properties

Organic peroxides are solid compounds, very sensitive to mechanical stress, such as friction and shock, as well as heat. They are non-volatile, and explode if heated to high temperature.[5]

Peroxide detection

Organic peroxides can be detected by using a solution of potassium iodide in water or acetic acid. If any peroxides are present in the liquid, the iodide solution will turn yellow at low levels of peroxides, and brown to purple-ish at high concentrations.

Handling

Safety

Compounds prone to forming dangerous peroxides should not be distilled to dryness, as the explosive peroxides will explode when dry. A good tip would be to add some high boiling solvent, like glycerol.

Storage

Compounds known to form peroxides should be kept in sealed bottles. BHT should be added as anti-oxidant, though a sheet of fresh metal, like copper can also be used. Sodium hydroxide can be added to precipitate any peroxides formed.

Disposal

Sensitive peroxides can be neutralized using a reducing agent, like sodium sulfite or ferrous sulfate. For ethers, metallic sodium can also be used, along with stirring or refluxing for better performance.

DO NOT ATTEMPT TO OPEN VERY OLD BOTTLES THAT HAVE PEROXIDES ON THE CAP!

See also

References

  1. http://www.ilpi.com/msds/ref/peroxide.html
  2. http://www.sigmaaldrich.com/chemistry/solvents/learning-center/peroxide-formation.html
  3. http://ccc.chem.pitt.edu/wipf/Web/16340.pdf
  4. http://www.baylor.edu/ehs/doc.php/203991.pdf
  5. http://ccc.chem.pitt.edu/wipf/Web/16340.pdf

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