Patent ID: 8119846
Filing Date: 2012-02-21
Classification: C07C

Abstract:
1. A process for separating an organic phase comprising mainly propyl bromide from a crude reaction mixture formed by free-radical catalyzed hydrobromination of propylene with hydrogen bromide, which process comprises: A) feeding cold water into an upper or mid-portion of a packed column having an upper portion, a mid-portion, and a lower portion; B) concurrently feeding said crude reaction mixture into an upper portion and/or mid-portion of said packed column so that the water contacts the crude reaction mixture to form a mixture of (i) an acidic aqueous phase comprising aqueous hydrogen bromide and (ii) an organic phase comprising propyl bromide; C) withdrawing said phases from said packed column, at a rate comparable to the feeds being made into said packed column in A) and B); D) separating said phases to form an upper acidic aqueous phase comprising aqueous hydrogen bromide superposed on a lower liquid organic phase comprising propyl bromide, and separating these upper and lower phases from each other, wherein the separated organic phase also contains entrained and/or dissolved aqueous phase; E) feeding the separated organic phase into a dryer column to strip aqueous phase from dried crude organic phase comprising propyl bromide; F) recovering the dried crude organic phase comprising propyl bromide as bottoms from the dryer column; and G) feeding the recovered bottoms from the dryer column to a splitter column, wherein isopropyl bromide is distilled from the bottoms as overhead and the overhead is recovered.