| 摘要 |
<p>1359950 Purification of chlorinated hydrocarbons; ethylene dichloride STAUFFER CHEMICAL CO 28 Nov 1972 [6 Dec 1971] 54971/72 Heading C2C Crude chlorinated organic compounds, such as ethylene dichloride, containing 2 or more C atoms are purified by passing to a light-ends separation zone 1 to separate an overhead fraction 3 containing low-boiling chlorinated impurities and water, and a bottoms fraction 4 containing the chlorinated organic compound and high boiling impurities, passing the overhead fraction 3 to a light-ends recovery zone comprising a condensation zone 8 and an accumulation zone 10 in communication with, and following, the condensation zone, whereby the low-boiling chlorinated impurities are condensed, accumulated and separated from water, and feeding an effective amount (i.e. sufficient to prevent or substantially inhibit corrosion) of an alkali metal material selected from MOH, M 2 CO 3 and MHCO 3 , and mixtures thereof, wherein M is Na, K or Li, to the overhead fraction at a point between the light-ends and the light-ends recovery zone, to the condensation zone at 14 or to the accumulation zone 10. The alkali metal is preferably fed in an amount stoichiometrically equivalent to or greater than the amount of HCl present in the system, e.g. as a solution having a concentration 0À05 to 25% by weight.</p> |
