Coproduction of a normal purity and ultra high purity volatile component from a multi-component stream.

摘要

A volatile component (A) with normal purity (24) and ultra high purity (42) is coproduced from a stream (10) containing a heavier component (B) and contaminated with a lighter impurity (I) which is more volatile than the volatile component by removing from a first distillation column (12) a steam (32) of the volatile component (A) which is substantially free of the lighter impurity (I) and then introducing this impurity-freed steam (32) to a second distillation column (34) for fractionation. The second distillation column (34) is equipped with a rectification section wherein the impurity-freed stream (32) is rectified and the volatile component (A) obtained in ultra high purity as an overhead (36). The volatile component (A) with normal purity (24) is obtained from the first distillation column (12) as an overhead (18). <IMAGE>