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Petroleum ether

Benzine redirects here. For the Rammstein single, see Benzin. For the aromatic compound, see benzene. For the automobile fuel (called benzine in many countries) see gasoline.

Petroleum ether

Other names

Benzine
Ligroine
Naphtha petroleum

Identifiers

CAS number

8032-32-4.

RTECS number

OI6180000

Properties

Molecular formula

Mixture of hydrocarbons

Molar mass

87 to 90 g/mol

Appearance

Colorless liquid

Density

0.625 to 0.660g/cm³, liquid

Melting point

Additional recommended knowledge

Recognize and detect the effects of electrostatic charges on your balance

< -73 °C

Boiling point

20 to 75 °C

Solubility in water

Insoluble

Hazards

Main hazards

Highly flammable
irritant

NFPA 704

R-phrases

R12, R38, R51/53,
R62, R65, R67

S-phrases

S9, S16, S23, S24,
S33, S62

Flash point

-18 °C

Related Compounds

Related compounds

naphtha, kerosene

Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)
Infobox disclaimer and references

Petroleum ether, also known as benzine, X4 or Ligroin, is a group of various volatile, highly flammable, liquid hydrocarbon mixtures used chiefly as nonpolar solvents.

Petroleum ether is obtained from petroleum refineries as the portion of the distillate which is intermediate between the lighter naphtha and the heavier kerosene. It has a specific gravity of between 0.6 and 0.8 depending on its composition.

Benzine should not be confused with benzene. Benzine is a mixture of alkanes, e.g., pentane, hexane, and heptane, whereas benzene is a cyclic, aromatic hydrocarbon, C₆H₆. Likewise, petroleum ether should not be confused with the class of organic compounds called ethers, which contain the -O- functional group.

During the Second World War some extermination camps experimented to kill people with benzine injections.^[1]

Ligroin

Ligroin is a refined saturated hydrocarbon petroleum fraction similar to petroleum ether used mainly as a laboratory solvent. It predominantly consists of C₇ through C₁₁ in the form of about 55% paraffins, 30% monocycloparaffins, 2% dicycloparaffins and 12% alkylbenzenes. It is nonpolar. Generally laboratory grade ligroin boils at 60 to 90 °C, but the following fractions of petroleum ether are commonly available: 30 to 40 °C, 40 to 60 °C, 60 to 80 °C, 80 to 100 °C and sometimes 100 to 120 °C. The 60 to 80 °C fraction is often used as a replacement for hexane.