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

Butyraldehyde

Butyraldehyde is a liquid with a characteristic, pungent, aldehyde odor.

CAS 123-72-8 C4H8O 72.11 g/mol Danger

01 · Identification

What Butyraldehyde is

Butyraldehyde is a liquid with a characteristic, pungent, aldehyde odor. Its molecular formula is C4H8O and its molecular weight is 72.11 g/mol. It boils at 74.8 °C, melts at -96.9 °C.

Under the GHS it carries the signal word Danger. It is classed as flammable agents - 3rd degree.

CAS number123-72-8
EC number204-646-6
Index number605-006-00-2
Molecular formulaC4H8O
Molecular weight72.11 g/mol
Chemical class Flammable agents - 3rd degree

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 Butyraldehyde
CodeHazard statement
H225 Highly flammable liquid and vapour.

Precautionary statements: P210, P233, P241, P242, P403

03 · Physical and chemical properties

Butyraldehyde 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 74.8 °C (166.6 °F) HSDB
75 °C (167 °F) at 760 mmHg CAMEO
Melting point -96.86 °C (-142.3 °F) HSDB
-98.89 °C (-146 °F) CAMEO
-99 °C (-146.2 °F) ICSC
Density 0.8016 g/cm³ HSDB
0.8 g/cm³ ICSC
0.803 g/cm³ at 20 °C CAMEO
Solubility Miscible with ethanol, ether, ethyl acetate, acetone, toluene, many other organic solvents andoils HSDB
Soluble in water; miscible with ethanol; very olubl ein acetone, benzene; slightly soluble in chloroform HSDB
In water, 7.10X10+4 mg/L at 25 °C at 25 °C HSDB
Vapor pressure 91.5 mmHg at 20 °C CAMEO
91.5075 mmHg at 20 °C ICSC
111 mmHg at 25 °C HSDB
Flash point -22.22 °C (-8 °F) HSDB
-6.67 °C (20 °F) CAMEO
-12 °C (10.4 °F) ICSC
Autoignition temperature 218.33 °C (425 °F) HSDB
230 °C (446 °F) CAMEO
Lower explosive limit (LEL) 1.9 % by volume HSDB
2.5 % by volume CAMEO
Upper explosive limit (UEL) 12.5 % by volume HSDB
Vapor density 2.5 (air = 1) HSDB
Odor threshold Odor threshold= 0.009 ppm HSDB
Odor Threshold Low: 0.005 [ppm] Haz-Map
Odor Threshold High: 9.0 [ppm] Haz-Map
Critical temperature and pressure 263.95 °C (507.1 °F) HSDB

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

04 · Handling and storage

Storing and handling Butyraldehyde

Storage conditions

On contact with air butyraldehyde is oxidized readily to the butyric acids. Therefore, storage under inert gas is mandatory.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Incompatible with oxidizing materials.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

A colorless liquid, BUTYRALDEHYDE can react with oxidizing materials. In contact with strong acids or bases it will undergo an exothermic condensation reaction. The dry aldehyde may undergo some polymerization reaction. Reacts vigorously with chlorosulfonic acid, nitric acid, sulfuric acid (oleum). [Sax, 9th ed., 1996, p. 607].

Source: CAMEO Chemicals

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

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