Process for purification of n-propyl bromide

摘要

Purification processes for separating n-propyl bromide from a crude reaction mixture comprising n-propyl bromide and isopropyl bromide which process comprises:
(I) washing at least a portion of the crude reaction mixture one or more times with a wash comprising an aqueous solution or aqueous suspension of at least one alkali metal hydroxide having a molar concentration in the range of 3 to 5 moles per liter, to form an aqueous phase and an organic phase, and then separating the phases thus formed;
(II) optionally, washing at least a portion of the organic phase from (I) with water to form an aqueous phase and an organic phase and then separating the phases thus formed;
(III) either
(A) when (I) is conducted and (II) is not conducted, distilling at least a portion of the organic phase from (I) one or more times; or
(B) when (I) and (II) are conducted, distilling at least a portion of the organic phase from (II) one or more times; and
(IV) forming a propyl bromide product mixture wherein the propyl bromide product mixture is comprised of at least 99.7 GC area % n-propyl bromide and no more than 0.05 GC area % isopropyl bromide.
Also provided is a composition of enhanced thermal stability which comprises a mixture of n-propyl bromide and isopropyl bromide. The mixture has an n-propyl bromide content of at least 99.7 GC area %, and an isopropyl bromide content of no more than 0.05 GC area %. The mixture, if subjected to storage in a closed chemically inert container at 60°C for at least 480 hours, has an APHA color of 10 or less while the mixture is devoid of any added stabilizer component.