Patent ID: 8664453
Filing Date: 2014-03-04
Classification: B01D,C07C

Abstract:
1. A process for recovering dichlorohydrin(s) from a mixture comprising dichlorohydrin(s); one or more compounds selected from the group consisting of chlorohydrins, ester(s) of chlorohydrin(s), monochlorohydrin(s), ester(s) of monochlorohydrin(s), ester(s) of dichlorohydrin(s), multihydroxylated-aliphatic hydrocarbon compound(s) and ester(s) of multi hydroxylated-aliphatic hydrocarbon compound(s); water; and optionally one or more substances comprising chlorinating agent(s), catalyst(s), ester(s) of catalyst(s), or heavy byproduct(s), wherein the process comprises: (a) providing a vapor and/or liquid phase mixture obtained from a hydrochlorination reaction comprising dichlorohydrin(s); one or more compounds selected from the group consisting of chlorohydrins, ester(s) of chlorohydrin(s), monochlorohydrin(s), ester(s) of monochlorohydrin(s), ester(s) of dichlorohydrin(s), multihydroxylated-aliphatic hydrocarbon compound(s) and ester(s) of multihydroxylated-aliphatic hydrocarbon compound(s); water, wherein the water present in the mixture is the water produced in the hydrochlorination reaction; and optionally one or more substances comprising chlorinating agent(s), catalyst(s), ester(s) of catalyst(s), or heavy byproduct(s); (b) distilling or fractionating the mixture of step (a) in at least a first separation unit operation to separate a lower boiling fraction comprising dichlorohydrin(s) and other lower boiling components from the mixture of step (a), to form a higher boiling fraction comprising the residue of the distillation or fractionation; wherein step (b) comprises: (b1) vaporizing an azeotropic mixture of dichlorohydrin(s) and water from the mixture of step (a) to separate a lower boiling fraction comprising at least dichlorohydrin(s) and water from the mixture of step (a); and (b2) condensing the low boiling fraction of step (b1) to form a liquid aqueous phase and a liquid organic phase comprising dichlorohydrin(s); or (ii) wherein step (b) further comprises: (b3) separating the liquid aqueous phase of step (b2) from the liquid organic phase of step (b2); and (b4) recycling at least some of the liquid aqueous phase of step (b3) to step (b1) and/or step (b2); (c) transferring the higher boiling fraction from step (b) to at least a second separation unit operation; and introducing a stripping agent into the higher boiling fraction in the at least second separation unit operation; wherein the stripping agent is an azeotroping agent for the dichlorohydrin(s); and wherein the stripping agent contacts the higher boiling fraction and strips dichlorohydrin(s) from the higher boiling fraction into a vapor phase; wherein a vapor fraction comprising dichlorohydrin(s) and stripping agent is produced in the at least second separation unit operation; and wherein the formation of heavy byproducts is minimized; (d) recovering at least a portion of the lower boiling fraction of step (b) and the vapor fraction of step (c); and (e) combining the lower boiling fraction produced in step (b) with the vapor fraction produced in step (c).