Water → HCID 91335, compound

A further improved and thus preferred embodiment of the process according to the invention is achieved in that a partial quantity (D") of the organic phase (D) leaving extraction stage (3) is separated and extracted countercurrently in an upstream, preferably multistage, extraction stage (2) with at least a partial quantity, preferably with the entire stream of (C) and the partial stream (D") is calculated in such a manner that the polyamine contained in (D") is as far as possible transferred into the aqueous phase leaving the extraction unit (2), the said aqueous phase, optionally after the addition of water from stream (Y) and/or auxiliary amine and/or further aqueous phase from stream (C) is introduced into extraction stage (3) and the organic phase (R) arising in (2), which is substantially composed of hydrophobic solvent and optionally auxiliary amine, is also introduced into extraction stage (3) and, as a constituent of the organic phase (B), is used as a solvent for the starting polyamine (A). The auxiliary amine used is preferably aniline and the polyamine mixture of the diphenylmethane series used is preferably a polyamine mixture of the kind obtained during acid-catalyzed aniline/formaldehyde condensation.

1. additionis introduced into extraction stage (3)

ORD record

ord-e109f28a98424656a49d1f61412fc87e

Source dataset

uspto-grants-1997_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05684180