1,2-Dichloroethane

1,2-Dichloroethane
1,2-Dichloroethane	1,2-Dichloroethane
IUPAC name 1,2-Dichloroethane
Other names Ethylene dichloride Ethane dichloride Dutch liquid, Dutch oil Freon 150
style="background: #F8EABA; text-align: center;" colspan="2" | Identifiers
CAS number	107-06-2 Y
ChemSpider	10
RTECS number	KI0525000
SMILES
style="background: #F8EABA; text-align: center;" colspan="2" | Properties
Molecular formula	C2H4Cl2
Molar mass	98.96 g mol−1
Appearance	Colorless liquid with characteristic odor
Density	1.253 g/cm³, liquid
Melting point	-35 °C, 238 K, -31 °F
Boiling point	84 °C, 357 K, 183 °F
Solubility in water	0.87 g/100 mL (20 °C)
Viscosity	0.84 mPa·s at 20 °C
style="background: #F8EABA; text-align: center;" colspan="2" | Structure
Dipole moment	1.80 D
style="background: #F8EABA; text-align: center;" colspan="2" | Hazards
R-phrases	R11 R45 R36/37/38
S-phrases	S45 S53
NFPA 704	75px 3 3 0
Flash point	13 °C
style="background: #F8EABA; text-align: center;" colspan="2" | Related compounds
Related haloalkanes	Methyl chloride Methylene chloride 1,1,1-Trichloroethane
Related compounds	Ethylene Chlorine Vinyl chloride
Y (what is this?)  (verify) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

The chemical compound 1,2-dichloroethane, commonly known by its old name of ethylene dichloride (EDC), is a chlorinated hydrocarbon, mainly used to produce vinyl chloride monomer (VCM, chloroethene), the major precursor for PVC production. It is a colourless liquid with a chloroform-like odour. 1,2-Dichloroethane is also used generally as an intermediate for other organic chemical compounds and as a solvent. It forms azeotropes with many other solvents, including water (b.p. 70.5 C) and other chlorocarbons.

History

In 1794, physician Jan Rudolph Deiman, merchant Adriaan Paets van Troostwijk, chemist Anthoni Lauwerenburg, and botanist Nicolaas Bondt, under the name of Gezelschap der Hollandsche Scheikundigen (Dutch: Society of Dutch Chemists), were the first to produce 1,2-dichloroethane from olefiant gas (oil-making gas, ethylene) and chlorine gas. Although the Gezelschap in practice did not do much in-depth scientific research, they and their publications were highly regarded. Part of that acknowledgement is that 1,2-dichloroethane has been called "Dutch oil" in old chemistry.

Production

Nearly 20 million tons of 1,2-dichloroethane are produced in the United States, Western Europe, and Japan. Production is primarily achieved through the iron(III) chloride-catalysed reaction of ethene (ethylene) and chlorine.

H₂C=CH₂ + Cl₂ → ClCH₂-CH₂Cl

1,2-dichloroethane is also generated by the copper(II) chloride-catalysed "oxychlorination" of ethylene:

H₂C=CH₂ + 2 HCl + ½ O₂ → ClCH₂-CH₂Cl + H₂O

In principle, it can be prepared by the chlorination of ethane and, less directly, from ethanol.

Uses

Vinyl chloride monomer (VCM) production

With approximately 80% of the world's consumption of 1,2-dichloroethane, the major use of 1,2-dichloroethane is in the production of vinyl chloride monomer (VCM, chloroethene) with hydrogen chloride as a byproduct. VCM is the precursor to polyvinyl chloride.

Cl-CH₂-CH₂-Cl → H₂C=CH-Cl + HCl

The hydrogen chloride can be re-used in the production of more 1,2-dichloroethane via the oxychlorination route described above.

Other uses

As a good apolar aprotic solvent, 1,2-dichloroethane is used as degreaser and paint remover. As a useful 'building block' reagent, it is used as an intermediate in the production of various organic compounds such as ethylenediamine. In the laboratory it is occasionally used as a source of chlorine, with elimination of ethene and chloride.

Via several steps, 1,2-dichloroethane is a precursor to 1,1,1-trichloroethane, which is used in dry cleaning. Historically, 1,2-dichloroethane was used as an anti-knock additive in leaded fuels.

Safety

1,2-dichloroethane is toxic (especially by inhalation due to its high vapour pressure), corrosive, highly flammable, and possibly carcinogenic. Its high solubility and 50-year half-life in anoxic aquifers make it a perennial pollutant and health risk that is very expensive to treat conventionally, requiring a method of bioremediation. Substitutes are recommended and will vary according to application. 1,3-dioxolane and toluene are possible substitutes as solvents. Dichloroethane is unstable in the presence of aluminium metal and, when moist, with zinc and iron. Molded plastic consumer products (e.g., toys and holiday decorations) are known to release 1,2-dichloroethane over time.

External links

• Gezelschap der Hollandsche Scheikundigen
• ChemicalLand compound database
• Environmental Chemistry compound database
• Merck Chemicals database
• National Pollutant Inventory - 1,2 Dichlorethane Fact Sheet
• Locating and estimating air emissions from sources of ethylene dichloride, EPA report EPA-450/4-84-007d, March 1984

az:1,2-dixloretan