VERFAHREN ZUR HERSTELLUNG VON 1,1-DIFLUOR-1-CHLORAETHAN

摘要

In the continuous prodn. of 1,1-difluoro-1-chloroethane (I) from 1, 1-difluoroethane (II) and Cl2 in the liquid phase by the action of high energy light, a (II) content of is not 10 wt.% is maintained in the liquid phase by addn. of (II). The content of (I) in the liq. phase is maintained at 40-80 wt.%. Chlorination is carried out at 0.5-5 bar and -30 degrees C to +50 degrees C. The liq. phase contains 1 wt.% F2ClC-CHCl2 and F2ClC-CH2Cl. The liq. phase is discharged continuously from the photoreactor and distilled fractionally, the fraction, i.e. mixt. of (I) and (II), with a b.pt. -25 degrees C at normal pressure, being recycled to the photoreactor. The formation of by-prods. and esp. of HF is minimised.