Peroxide Forming Chemicals

Certain chemicals can form dangerous peroxides on exposure to air and light. Since they are sometimes packaged in an atmosphere of air, peroxides can form even though the containers have not been opened. Peroxides may detonate with extreme violence when concentrated by evaporation or distillation, when combined with other compounds, or when disturbed by unusual heat, shock or friction. Formation of peroxides in ethers is accelerated in opened and partially emptied containers. Refrigeration will not prevent peroxide formation and stabilizers will only retard formation.

Peroxide formation may be detected by visual inspection for crystalline solids or viscous liquids, or by using chemical methods or specialized kits for quantitative or qualitative analysis. If it is suspected that peroxides have formed, the container should not be opened, even to test as any peroxides deposited on the threads of the cap could detonate. Call EHS (5512) for management/disposal of these containers.

As chemicals with the potential to form peroxides have limited shelf lives, prudent practice would be to purchase very small amounts for delivery as close to time of intended use as possible. Containers should be labeled with date of arrival on campus. The date of opening the container and the date for disposal, based on the following table, should be added at the time the container is opened.

Examples of Peroxidizable Compounds

 

Discard after Three Months (Peroxide Hazard simply as a result of Storage)

        Divinyl acetylene

        Divinyl ether

        Isopropyl ether

        Potassium metal

        Sodium amide

        Vinylidene chloride

 

Discard after One Year (Peroxide Hazard as a result of Concentration)

        Acetal

        Cumene

        Cyclohexene

        Cyclooxyene

        Cyclopentene

        Diacetylene

        Dicyclopentadiene

        Diethyl ether

        Diethylene glycol dimethyl ether (diglyme)

        Dioxane

        Ethylene glycol dimethyl ether (glyme)

        Furan

        Methyl acetylene

        Methylcyclopentane

        Methyl isobutyl ketone (MIBK)

        Tetrahydronaphtalene (Tetralin)

        Tetrahydrofuran

        Vinyl ethers

 

Discard after one year (Peroxide Hazard as a result of Polymerization*)

        Acrylic Acid

        Acrylonitrile

        Butadiene

        Chloroprene

        Chlorotrifluoroethylene

        Methyl methacrylate

        Styrene

        Tetrafluoroethylene

        Vinyl acetylene

        Vinyl acetate

        Vinyl chloride

        Vinyl pyridine

* Under storage conditions in the liquid state the peroxide-forming potential increases and certain of these monomers (especially butadiene, chloroprene, and tetrafluoroethylene) should be discarded after three months.

Chemicals with similar sounding names that are not identified as peroxide formers: