Ethylene carbonate (sometimes abbreviated EC) is the organic compound with the formula (CH2O)2CO. It is classified as the cycliccarbonate ester of ethylene glycol and carbonic acid. At room temperature (25 °C) ethylene carbonate is a transparent crystalline solid, practically odorless and colorless, and somewhat soluble in water. In the liquid state (m.p. 34-37 °C) it is a colorless odorless liquid.[3]
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:[4][5]
(CH2)2O + CO2 → (CH2O)2CO
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:[6]
The transesterfication of ethylene carbonate by methanol can be catalyzed by a high surface area (thermally exfoliated) graphitic carbon nitride (g-C3N4) materials. This method reduces the chance of metal or halide contamination, and can offer yields of up to 60% at a temperature of 393 K.[7]
Ethylene carbonate was a universal component of an electrolyte in earlier (prior to ca. 2010) lithium-ion batteries, since it is responsible for the formation of the solid electrolyte interphase on the anode. Since EC is solid at room temperature, it was mixed with propylenecarbonate. As dimethylcarbonate and other dialkylcarbonates became commercially available, they replaced ethylene carbonate in some modern lithium-ion batteries.
A typical sodium intercalation type battery would use an electrolyte consisting of: fluoroethylene carbonate (FEC) (99%), metallic Na (99.9%), and 1.0 M sodium perchlorate (NaClO4) solutions in ethylene carbonate and diethyl carbonate (EC/DEC), 1:1 v/v% battery-grade, mixed with FEC (10% by weight).[11]
^Comerford, James W.; Ingram, Ian D. V.; North, Michael; Wu, Xiao (2015). "Sustainable metal-based catalysts for the synthesis of cyclic carbonates containing five-membered rings". Green Chemistry. 17 (4): 1966–1987. doi:10.1039/C4GC01719F. S2CID96255105.
^Bhalchandra M. Bhanage; Shin-ichiro Fujita (2003). "Transesterification of urea and ethylene glycol to ethylene carbonate as an important step for urea based dimethyl carbonate synthesis". Green Chemistry. 5 (4): 429–432. doi:10.1039/b304182d. S2CID97286880.
^Ralph P. Seward; Ernest C. Vieira (1958). "The Dielectric Constants of Ethylene Carbonate and of Solutions of Ethylene Carbonate in Water, Methanol, Benzene and Propylene Carbonate". J. Phys. Chem. 62 (1): 127–128. doi:10.1021/j150559a041.
^Richard Payne; Ignatius E. Theodorou (1972). "Dielectric properties and relaxation in ethylene carbonate and propylene carbonate". J. Phys. Chem. 76 (20): 2892–2900. doi:10.1021/j100664a019.