13  5,679,840  14  The third variant  of the process according  to the invention  is an  embodiment which  is improved in this  respect. Starting  By means of the  preferred use of  a  polyamine with the  composition  of the second  subproduct (L)  as a  constituent  of  With polyarnine  as a  constituent of organic  phase (0),  phases (M) and  (N)  leaving process stage  (7) have a higher  polyamine concentration  than use of an organic  phase (0)  without polyamine,  which is energetically  more favorable  for  implementation  of the process according  to the inven› tion.  A partial  introduction  of initial polyarnine  (A) to separa- tion stage  (6)  via  aqueous phase (C)  generally causes  an  increase in the polyamine  concentration  in (D) and thus a  decrease in energy  requirements. When  implementing  the  process, however,  this reduction is  associated with  a wors› ening in the qualitative  separation results  for the first sub- product (G), due  to the  establishment  of an  equilibrium  between the polyamine  in aqueous phase  (C) and the  polyamine  in organic phase  (D), so that use is  made of this  possibility only to  a small extent or  in cases where there  are  correspondingly  low  requirements  with respect to separation  results.  The effect is particularly  useful  if  the  components sepa› rated with (G) are  present in only low  concentration  in the  initial mixture (A)  and/or are relatively  highly enriched in  fraction (G), e.g.  during separation  according to the  inven› tion of polyamine  mixtures from the  diphenylmethane  series.  Use of an organic  phase (0) without  polyamine results  in  a  polyarnine fraction  in the aqueous  phase  (N)  leaving  extraction stage (7)  in which the relative  enrichment  of the  components preferentially  contained in this  phase is specifi› cally increased and  maximized beyond  the enrichment pro› duced in aqueous  phase (H), and the  concentration  of the  components enriched  in (G) can be  minimized,  at the  expense of the  polyarnine concentration  in the aqueous  phase.  Using the second  variant of the process  according to the  invention, the relative  enrichment  or depletion of the  two  polyarnine fractions  finally produced  can be specifically  varied and maximized.  In  addition to this qualitatively  high  versatility and power,  the second variant  also offers, at least  for the second polyamine  fraction  (L),  an  energetically  favorable embodiment.  The expense associated  with recov› ering the first polyamine  fraction (G) increases  more,  however, in relative  terms the smaller  is the amount of  (G)  with respect to polyamine  mixture (A) used,  because the  remaining concentration  of polyarnine (G)  is  correspond› ingly lower in organic  phase (D) which  has to be worked  up  by distillation.  Organic phase (0)  consists in general  of auxiliary amine  and optionally polyamine,  the latter preferably  having the  composition  of the second process  subproduct  (L).  A second variant  of the process according  to the invention  is more  advantageous  and is preferred as  an  embodiment.  In  this  variant,  in addition, the  relative enrichment  of the  components preferentially  contained in second  polyarnine  fraction  (L)  can also be specifically  varied, largely indepen› dently of the first  product fraction,  by extracting the  aqueous  phase (H) produced  in extraction stage  (6),  or at least some  of it. in a  downstream extraction  stage (7) operating  on the  counterflow principle,  using organic phase  (0).  Aqueous phase  (N)  resulting from stage  (7)  is taken to  neutralization  stage  (8).  Organic phase  (M)  resulting from stage  (7)  is added to  organic phase (B)  used in extraction  stage  (6).  Basically, it is also  possible to increase  the molarity by  removing water from  (H)  in a distillation procedure.  The molarity of  the aqueous phase  used in downstream  extraction stage  (7)  is in general greater  than that of aqueous  phase  (H)  leaving extraction  stage  (6).  Basically. it is  possible, however,  to modify both  the molarity and  the  degree of protonation,  to improve the  separating power  according to the  process. by adding  aqueous acid and/or  water.  optionally also auxiliary  amine, to the aqueous  phase.  By admixing amounts  of the second polyamine  fraction  (L) either as a substream  of  (J)  or as a substream  of (L) to  the initial arylamine  (A).  its relative  concentration  of com› ponents of (G) can  be lowered and thus  the lower limit of  these components  in the second  subproduct (L) achievable  according to this  first variant can be  shifted via the partition  equilibrium. The  only slight  improvement  in separating  power produced  in  this  way may be sufficient  for certain  applications,  but it generally  places a restriction  on the  throughput of  (A).  The proportion of  these components  remaining in the  second polyamine  fraction  (L), however.  are not minimized  in an  equivalent manner  in  accordance with this  first variant,  but are relatively  depleted in a variable  manner only down  to a  concentration whose  lower limit depends  on the char› acteristic partition  equilibrium,  for the particular  process  parameters,  of the polyarnine  components from  (A) between  organic phase  (B)  on entering extractor  (6)  and aqueous  phase  (H)  on leaving extractor  (6).  In  the simplest and  general case, organic  phase  (0)  is  formed from at least  a  substream of stream  (F)  and option- ally further auxiliary  amine and/or polyamine,  for example  a  substream of  (L).  Similarly, stream  (0)  may be formed  from a substream  of  (F)  and a substream  (J")  of stream  (J),  containing polyarnine  mixture  (L)  in addition to optional  auxiliary amine.  By means of the  possible addition  of  auxiliary amine,  described elsewhere,  before or in neutral› ization stage  (8),  an organic phase  (J)  is produced with  a  composition which  corresponds  by and large to  organic  phase  (0),  so that it can be  used, preferably  after passage  through washing  stage  (9),  as substream  (J"),  directly and  virtually without  any further additives,  as organic phase (0)  in process stage  (7).  organic phase (0),  the relative enrichment  of the polyarnine  components preferentially  contained in the  aqueous phase  (N)  leaving separating  stage  (7),  and thus the second  polyarnine fraction  (L),  can be varied and  maximized  at a  higher and thus  advantageous concentration  due to estab› lishing an equilibrium  with  self-amplification  of the sepa› rating effect.  In  particular, in the  first polyamine  fraction  (G),  the  relative enrichment  of the  components preferentially  con› tained in this fraction  can be specifically  varied and maxi› mized.  Using this variant  of the process  according to the  invention, considerable  separating power  is produced during  the  fractionation  of polyarnine mixtures  and numerous sepa› ration problems  are  satisfactorily solved.  In  the last stage of optionally  multi-stage distillation  stage  (12)  the second polyarnine  subproduct  (L)  is separated and  collected  in  process product  tank  (14).  The organic phase  produced during  neutralization  is sepa› rated as stream  (J),  optionally washed  with water in washing  stage  (9)  and worked up in  distillation stage  (12).  The aqueous phase  produced during  neutralization  is  separated and collected  in waste water container  (15).  Aqueous phase  (H).  optionally after the  addition of aux› iliary amine, is reacted  in  neutralization  stage  (8)  with the  aqueous solution  of a strong base,  preferably caustic  soda  solution. to neutralize  the acid contained  therein. 