Process for the removal of contaminant from a hydrochlorofluoroolefin by extractive distillation

摘要

A method for removing a contaminant from a hydrochlorofluoroolefin (such as trans-1,1,1-trifluoro-3-chloro-2-propene (1233zd(E))) includes extracting a chlorofluorocarbon (such as trichlorofluoromethane (R11)) from a mixture comprising the hydrochlorofluoroolefin and the chlorofluorocarbon using extractive distillation in the presence of an extractive solvent comprising a chlorinated compound to form a purified hydrochlorofluoroolefin. This separation method provides for removal of a contaminant, such as R11, from a hydrochlorofluoroolefin, such as 1232zd(E), which are not separable by conventional distillation methods. The method may employ a process utilizing two distillation columns, for example, a first extractive distillation column and a second solvent recovery column, which allows for recycle of the extractive solvent to the first extractive distillation column.

主权项

1. A method for removing a contaminant from a hydrochlorofluoroolefin comprising:
extracting a chlorofluorocarbon from a mixture comprising a hydrochlorofluoroolefin and the chlorofluorocarbon using extractive distillation in the presence of an extractive solvent comprising an organochloride selected from the group consisting of carbon tetrachloride, chloroform, methyl chloroform, and mixtures thereof to form a purified hydrochlorofluoroolefin.