To readily fractionate and separate the subject mixture with a good separation efficiency by extracting an aromatic polyamine mixture with a two-phase system comprising a specific solvent phase and an aqueous phase according to the countercurrent principle, distilling the organic phase, neutralizing the aqueous phase, then extracting the neutralized aqueous phase and distilling the resultant organic phase.
An aromatic polyamine mixture is mixed with a two-phase system comprising a hydrophobic phase consisting of (A1) an aromatic auxiliary amine and, as necessary, (A2) a polyamine and an aqueous phase consisting of water, a strong acid and, as necessary, the components A1 and A2 to carry out a first extraction according to the countercurrent principle and provide a first aqueous phase and a first organic phase. The resultant first organic phase is distilled to afford a first fraction consisting essentially of the component A1 and a distillation residue consisting essentially of the component A2. The first aqueous phase is subsequently neutralized with a base and the phase separation of the resultant mixture is conducted to provide a second aqueous phase consisting essentially of a neutral base and a second organic phase consisting essentially of the components A1 and A2. The second organic phase is distilled and separated into a distillate consisting essentially of the component A1 and a distillation residue consisting essentially of the component A2, and then fractionated and purified.
MIHIYAERU BUROTSUKERUTO
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