| 摘要 |
Process for the destillative purification of fluoroethylene carbonate Crude fluoroethylene carbonate obtained by the fluorination of ethylene carbonate and elemental fluorine containing not more than 5 % by weight of HF is purified by at least two subsequent distillation steps. The bulk of HF can be removed, if desired,in a preliminary HF removal step, e.g. by stripping,before performing the distillation. Further,if desired, a second HF removal step can be performed by contacting the crude mixture or the distillate obtained after the first distillation step with an adsorbent for HF, e.g. silica gel. The distillation can be performed batch wise. It is preferred to perform it continuously. It yields purified fluoroethylene carbonate with an HF content of equal to or less than 30 ppm. The purified fluoroethylene carbonate can be applied as solvent additive for lithium ion batteries.
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