41  5,886,235  42  wherein  R 2  represents a substituted or unsubstituted  divalent hydrocarbon radical containing from 4 to 40  carbon atoms or greater,  W  represents a substituted or  unsubstituted monovalent hydrocarbon radical contain› ing from 1 to 18 carbon atoms or greater,  X"  represents  an oxygen  (0)  atom, a substituted or unsubstituted  divalent nitrogen (N) atom-containing radical, a sub› stituted or unsubstituted divalent sulfur (S) atom- As  used herein, the term "substituted" is contemplated to 65  include all permissible substituents of organic compounds  unless otherwise indicated. In a broad aspect, the permis- For purposes of this invention, the term "hydrocarbon" is  contemplated to include all permissible compounds having  at least one hydrogen and one carbon atom. Such permis› sible compounds may also have one or more heteroatoms. In  a broad aspect, the permissible hydrocarbons include acyclic  (with or without heteroatoms) and cyclic, branched and  unbranched, carbocyclic and heterocyclic, aromatic and  nonaromatic organic compounds which can be substituted or  unsubstituted.  An alternate method of transferring acidity from the  reaction product fluid to an aqueous fraction is through the  intermediate use of a heterocyclic amine which has a fluo› rocarbon or silicone side chain of sufficient size that it is  immiscible in both the reaction product fluid and in the  aqueous fraction. The heterocyclic amine may first be con› tacted with the reaction product fluid where the acidity  present in the reaction product fluid will be transferred to the  nitrogen of the heterocyclic amine. This heterocyclic amine  layer may then be decanted or otherwise separated from the  reaction product fluid before contacting it with the aqueous  fraction where it again would exist as a separate phase. The  heterocyclic amine layer may then be returned to contact the  reaction product fluid.  wherein  R  1  represents a substituted or unsubstituted  trivalent hydrocarbon radical containing from 4 to 40  carbon atoms or greater, each  X’  is the same or different  and represents an oxygen  (0)  atom, a substituted or  unsubstituted divalent nitrogen (N) atom-containing  radical, a substituted or unsubstituted divalent sulfur  (S)  atom-containing radical or a substituted or unsub› stituted divalent hydrocarbon radical containing from 2  to 40 carbon atoms or greater, provided at least one  X’  is other than a substituted or unsubstituted divalent  hydrocarbon radical containing from 2 to 40 carbon  atoms or greater and at least one  X’  is other than an  oxygen  (0)  atom, and each d is the same or different  and is a value of 0 or 1, provided that the normal  valencies of  R  1 ,  N’ and phosphorus  (P)  are satisfied;  (ii) a diorganophosphorus ligand represented by the for› mula:  It is to be understood that while it may be preferred to  employ only one free heterocyclic nitrogen compound at a  time in any given process, if desired, mixtures of two or  more different free heterocyclic nitrogen compounds may  also be employed in any given process. Moreover the  amount of such free heterocyclic nitrogen compounds  present during harsh conditions, e.g., the vaporization  procedure, need only be that minimum amount necessary to  furnish the basis for at least some minimization of such  catalyst deactivation as might be found to occur as a result  of carrying out an identical metal catalyzed liquid recycle  hydroformylation process under essentially the same  conditions, in the absence of any free heterocyclic nitrogen  compound during vaporization separation of the aldehyde  product. Amounts of such free heterocyclic nitrogen com› pounds ranging from about 0.01 up to about 10 weight  percent, or higher if desired, based on the total weight of the  reaction product fluid to be distilled should be sufficient for  most purposes.  1.  A  process for separating one or more phosphorus acidic  compounds from a reaction product fluid containing said one  or more phosphorus acidic compounds, a metal› organophosphorus ligand complex catalyst and optionally  free organophosphorus ligand which process comprises  treating said reaction product fluid with water sufficient to  remove at least some amount of said one or more phospho- rus acidic compounds from said reaction product fluid,  wherein said reaction product fluid comprises an organic  phase and said water comprises a separate aqueous or water  phase, and wherein said metal-organophosphorus ligand  complex catalyst comprises a Group 8, 9 or 10 metal  complexed with an organophosphorus ligand selected from  the following:  Thus the possibility of metal catalyst deactivation due to  such harsh conditions is said to be minimized or prevented  by carrying out such distillation of the desired product from  the metal-organopolyphosphorus catalyst containing reac› tion product fluids in the added presence of a free hetero› cyclic nitrogen compound having a five or six membered  heterocyclic ring consisting of 2 to 5 carbon atoms and from  2 to 3 nitrogen atoms, at least one of said nitrogen atoms  containing a double bond. Such free heterocyclic nitrogen  compounds may be selected from the class consisting of  diazole, triazole, diazine, and triazine compounds, such as,  e.g., benzimidazole or benzotriazole, and the like. The term  "free" as it applies to said heterocyclic nitrogen compounds  is employed therein to exclude any acid salts of such  heterocyclic nitrogen compounds, i.e., salt compounds  formed by the reaction of any phosphorus acidic compound  present in the reaction product fluid with such free hetero- cyclic nitrogen compounds as discussed herein above.  We claim:  sible substituents include acyclic and cyclic, branched and  unbranched, carbocyclic and heterocyclic, aromatic and  nonaromatic substituents of organic compounds. Illustrative  substituents include, for example, alkyl, alkyloxy, aryl,  aryloxy, hydroxy, hydroxyalkyl, amino, aminoalkyl, halo› gen and the like in which the number of carbons can range  from 1 to about 20 or more, preferably from 1 to about 12.  The permissible substituents can be one or more and the  same or different for appropriate organic compounds. This  invention is not intended to be limited in any manner by the  permissible substituents of organic compounds.  intermediate rhodium species that was formed during vapor› ization separation as mentioned above, thereby reforming  the active catalyst in the hydroformylation reactor.  (i) a monoorganophosphorus ligand represented by the  formula: 