Patent ID: 7268262
Filing Date: 2007-09-11
Classification: C07C,Y02P

Abstract:
1. A method for recovering trans-1,2-dichloroethene from a liquid composition comprising the stereoisomers trans-1,2-dichloroethene and cis-1,2-dichloroethene, and contaminating amounts of other chlorinated hydrocarbons, comprising: (a) distilling said liquid composition in a first distillation zone; (b) removing first distillate comprising said stereoisomers trans-1,2-dichloroethene and cis-1,2-dichloroethene, and chlorinated hydrocarbons having a lower boiling temperature than said stereoisomers from said first distillation zone; (c) distilling at least a portion of the first distillate in a second distillation zone, and removing a liquid stream comprising said stereoisomers from the second distillation zone; (d) introducing at least a portion of the liquid stream comprising said stereoisomers removed from the second distillation zone into a reactive distillation zone containing organic free-radical initiator; (e) isomerizing cis-1,2-dichloroethene to trans-1,2-dichloroethene in said reactive distillation zone; and (f) recovering substantially pure trans-1,2-dichloroethene product from said reactive distillation zone.