Diethyl carbonate
- Diethyl
- Diatol
Colorless liquid with ethereal odor >
Liquid
0.9764 g · cm -3
-43 ° C
125.8 ° C>
11 hPa ( 20 ° C)
- Practically insoluble in water
- Soluble in ethanol, diethyl ether and chloroform
1.384 at 20 ° C.
Attention
Template: Infobox chemical / molecular formula search available
Diethyl carbonate (also Diatol or diethyl carbonate ) is an organic chemical compound. At room temperature, it is in the form of a clear, ethereal smelling liquid.
Representation and extraction
They are prepared by the reaction of phosgene with ethanol. A more recent method starts from urea, in which the reaction with ethanol at 180 ° C for Yttriumkatalysatoren occurs.
Properties
Physical Properties
Diethyl carbonate is a colorless and low-viscosity liquid, boiling at atmospheric pressure at 126 ° C. The vapor pressure function is given by Antoine corresponding log10 (P) = A- ( B / ( T C )) ( P in bar, T in K) with A = 4.77616, B = 1721.904 and C = -37.959 in temperature range from 263 to 399 K. the critical temperature is 296 ° C, the critical pressure at 34,6 bar. The heat capacity is at 21 ° C 210.9 J · mol -1 · K -1 or 1.78 J · g -1 · K -1.
Chemical Properties
Diethyl carbonate decomposes at higher temperatures to form carbon dioxide, ethanol, and ethylene. The decomposition reaction follows a first order rate law. With an activation energy of 195 kJ · mol -1 and a Arrheniusfaktor 1.15 · 1013 s- 1, the half-life of the decomposition arise at 270 ° C and 95 h at 310 ° C and 5 h at 360 ° C and 23 min.
Safety characteristics
Diethyl forms inflammatory vapor -air mixtures. The compound has a flash point below 25 ° C. The explosive range is between 1.4 vol% (69 g/m3) as the lower explosive limit ( LEL) and 11.7 % by volume (570 g/m3 ) and upper explosive limit (UEL ). The marginal gap width was determined to be 0.83 mm. The result is thus a mapping in the explosion group IIB. The ignition temperature is 445 ° C. The fabric falls within the temperature class T2.
Use
Diethyl carbonate is used as a solvent for cellulose nitrate and ether synthetic and natural resins. In addition, it is used in organic synthesis, for example in the Carboethoxylierung, and in synthesis of heterocycles.
Furthermore, it results from the " Controls" phosgene. This occurs from the decomposition of chloroform under supply of oxygen and the influence of light in addition to hydrochloric acid. The addition of ethanol, chloroform can be made " phosgensicher ", because with the alcohol, the phosgene reacts immediately to harmless diethyl carbonate.
The compound is also a component of electrolyte solutions for lithium batteries.