Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

1,4-dioxane

1,4-dioxane is a colorless liquid or solid (below 53 degrees F) with a faint pleasant odor.

CAS 123-91-1 C4H8O2 88.11 g/mol Danger

1,4-dioxane Safety Data Sheet →

01 · Identification

What 1,4-dioxane is

1,4-dioxane is a colorless liquid or solid (below 53 degrees F) with a faint pleasant odor. Its molecular formula is C4H8O2 and its molecular weight is 88.11 g/mol. It boils at 101 °C, melts at 11.8 °C.

Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).

CAS number123-91-1
EC number204-661-8
Index number603-024-00-5
Molecular formulaC4H8O2
Molecular weight88.11 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

Other names for 1,4-dioxane

  • dioxane
  • Di(Ethylene Oxide)
  • Diethylene Dioxide
  • 1,4-Diethylene Dioxide
  • Diethylene Ether
  • Diethylene Oxide
  • Diokan
  • 1,4-Dioxacyclohexane
  • Dioxan
  • 1,4-Dioxan
  • Dioxane-1,4
  • 1, 4-Dioxane
  • 1,4-Dioxin, Tetrahydro-

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to 1,4-dioxane
CodeHazard statement
H225 Highly flammable liquid and vapour.
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H335 May cause respiratory irritation.
H319 Causes serious eye irritation.

Supplemental EU statements: EUH019, EUH066

Precautionary statements: P201, P210, P233, P241, P242, P264, P280, P305, P308, P313, P337, P338, P403

03 · Physical and chemical properties

1,4-dioxane properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Boiling point 101.2 °C (214.2 °F) HSDB
101.11 °C (214 °F) NIOSH
101.11 °C (214 °F) at 760 mmHg CAMEO
Melting point 11.75 °C (53.2 °F) HSDB
11.67 °C (53 °F) NIOSH
11.78 °C (53.2 °F) CAMEO
Density 1.03 g/cm³ NIOSH
1.0337 g/cm³ at 20 °C HSDB
1.036 g/cm³ at 20 °C CAMEO
Solubility Miscible with most organic solvents HSDB
Miscible with aromatic hydrocarbons and oils. HSDB
In water, >800 g/L at 25 °C at 25 °C HSDB
Vapor pressure 29 mmHg NIOSH
29 mmHg at 20 °C CAMEO
38.1 mmHg at 25 °C HSDB
Flash point 18.33 °C (65 °F) HSDB
12.78 °C (55 °F) NIOSH
12.22 °C (54 °F) CAMEO
Autoignition temperature 180 °C (356 °F) HSDB
Lower explosive limit (LEL) 2 % by volume HSDB
Upper explosive limit (UEL) 22 % by volume HSDB
Vapor density 3.03 (air = 1) HSDB
3 (air = 1) ICSC
Odor threshold ...Air threshold of recognition at 170 ppm. This odor recognition threshold allows for dioxane to be detected before acute toxic effects occur. HSDB
Odor Threshold Low: 0.8 [ppm] Haz-Map
Odor Threshold High: 172.0 [ppm] Haz-Map
Critical temperature and pressure 312 °C (593.6 °F) HSDB

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Handling and storage

Storing and handling 1,4-dioxane

Storage conditions

Store in a cool, dry, well-ventilated location. Store away from heat, oxidizing materials, and sunlight. Outside or detached storage is preferred. Inside storage should be in a standard flammable liquids storage warehouse, room, or cabinet.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Pure, dry, o- and hydroperoxide-free dioxane rapidly forms hydroperoxide on contact with air.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

DIOXANE is a flammable liquid; when exposed to air it undergoes autooxidation with formation of peroxides. In the distillation process peroxides will concentrate causing violent explosion. The addition complex with sulfur trioxide (1:1) sometimes decomposes violently on storing at room temperature [Sisler, H. H. et al., Inorg. Synth., 1947, 2, p. 174]. Evaporation of boron trifluoride in aqueous dioxane with nitric acid led to an explosion upon addition of perchloric acid [MCA Guide, 1972, p. 312]. Explosive reaction with Raney nickel catalyst above 210 °C {Mozingo R., Org. Synth., 1955, Coll. Vol. 3, p. 182].

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 1,4-dioxane in the storage compatibility matrix →

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