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

Furan

Furan is a colorless liquid, turns brown upon standing with an ethereal odor.

CAS 110-00-9 C4H4O 68.07 g/mol Danger

01 · Identification

What Furan is

Furan is a colorless liquid, turns brown upon standing with an ethereal odor. Its molecular formula is C4H4O and its molecular weight is 68.07 g/mol. It boils at 31.5 °C, melts at -85.6 °C, is soluble in water.

Under the GHS it carries the signal word Danger. It is classed as carcinogens.

CAS number110-00-9
EC number203-727-3
Index number603-105-00-5
Molecular formulaC4H4O
Molecular weight68.07 g/mol
Chemical class Carcinogens

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 Furan
CodeHazard statement
H224 Extremely 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>.
H341 Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H332 Harmful if inhaled.
H302 Harmful if swallowed.
H373 May cause damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H315 Causes skin irritation.
H412 Harmful to aquatic life with long lasting effects.

Supplemental EU statements: EUH019

Precautionary statements: P201, P210, P233, P241, P242, P260, P264, P270, P271, P273, P280, P301, P302, P304, P308, P312, P313, P314, P330, P332, P352, P403, P501

03 · Physical and chemical properties

Furan 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 31.5 °C (88.7 °F) HSDB
32.22 °C (90 °F) at 758 mmHg CAMEO
31.3 °C (88.3 °F) ICSC
Melting point -85.61 °C (-122.1 °F) HSDB
-86.11 °C (-123 °F) CAMEO
-85.6 °C (-122.1 °F) ICSC
Density 0.9514 g/cm³ at 20 °C HSDB
0.9731 g/cm³ at 19.4 °C HSDB
0.9371 g/cm³ at 19.4 °C CAMEO
Solubility Soluble in alcohol and ether HSDB
Slightly soluble in chloroform; very soluble in ethanol, ether; soluble in acetone, benzene HSDB
In water, 1X10+4 mg/L at 25 °C at 25 °C HSDB
Vapor pressure 493 mmHg at 20 °C CAMEO
493.541 mmHg at 20 °C ICSC
600 mmHg at 25 °C, from experimentally derived coefficients HSDB
Flash point -35.56 °C (-32 °F) HSDB
-35 °C (-31 °F) ICSC
Less than 32F (EPA, 1998) CAMEO
Autoignition temperature 390 °C (734 °F) ICSC
Lower explosive limit (LEL) 2.3 % by volume % by vol HSDB
2.3 % by volume CAMEO
Upper explosive limit (UEL) 14.3 % by volume % by vol HSDB
14.3 % by volume CAMEO
Vapor density 2.3 (air = 1) HSDB
Critical temperature and pressure 214 °C (417.2 °F) HSDB

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

04 · Handling and storage

Storing and handling Furan

Storage conditions

Before entering confined space where this chemical may be present, check to make sure that an explosive concentration does not exist. Store in an explosion-proof refrigerator. Keep in a tightly closed container under an inert atmosphere and protect from light for long-term storage. A regulated, marked area should be established where this chemical is handled, used, or stored ...

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Violent reaction with acids, oxidizers. Unless stablized with an inhibitor, air exposure forms unstable peroxides.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

FURAN is sensitive to heat and may turn brown upon standing. This compound may be light sensitive. When uninhibited, this compound forms explosive peroxides on exposure to air. This chemical may react with oxidizers, acids, peroxides and oxygen. It resinifies on evaporation or when in contact with mineral acids, but it is stable in alkalis. (NTP, 1992).

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Furan in the storage compatibility matrix →

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