Ethylene carbonate
Ethylene carbonate is the organic compound with the formula 2CO. It is classified as the carbonate ester of ethylene glycol and carbonic acid. At room temperature ethylene carbonate is a transparent crystalline solid, practically odorless and colorless, and somewhat soluble in water. In the liquid state it is a colorless odorless liquid.Production and reactions
Ethylene carbonate is produced by the reaction between ethylene oxide and carbon dioxide. The reaction is catalyzed by a variety of cations and complexes:
In the laboratory, ethylene carbonate can also be produced from the reaction of urea and ethylene glycol using zinc oxide as a catalyst at a temperature of 150 °C and a pressure of 3 kPa:
Ethylene carbonate may be converted to dimethyl carbonate via transesterification by methanol:
Dimethyl carbonate may itself be similarly transesterified to diphenyl carbonate, a phosgene-substitute:Applications
Ethylene carbonate is used as a polar solvent with a molecular dipole moment of 4.9 D, only 0.1 D lower than that of propylene carbonate.
It can be used as a high permittivity component of electrolytes in lithium batteries and lithium-ion batteries. Other components like diethyl carbonate, ethyl methyl carbonate, dimethyl carbonate and methyl acetate can be added to those electrolytes in order to decrease the viscosity and melting point.
Ethylene carbonate is also used as plasticizer, and as a precursor to vinylene carbonate, which is used in polymers and in organic synthesis.
