49  5,744,650  50  Example  4  Example  5  Example  2  Example  6  Example  3  TABLEB  TABLE  A  A  butyraldehyde  solution  was  prepared  containing  1.0  percent  by  weight  of  benzotriazole.  The  solution  was  then  analyzed  by Gas  Chromatography  for  benzotriazole  content  to  serve  as a  reference  sample.  To the  solution  prepared  in  the  previous  step  was  added  0.25  mole  equivalents  of  phosphorous  acid  (H:J>()$_{3}$ ).  In a  one  pint  glass  bottle  was  added  50  grams  of the  butyraldehyde  solution  containing  benzotriazole  and  50  grams  of a  pH 7.  0.2  molar  sodium  phosphate  buffer  solution.  The  mixture  was  stirred  for 15  minutes  and  then  transferred  to a  separatory  funnel.  The  aqueous  layer  was  then  separated  from  the  aldehyde  layer.  The  aqueous  layer  was  analyzed  for H$_{3}$ P0$_{3 }$ content  by  Ion  Chromatography.  The  aldehyde  layer  was  analyzed  for ben› zotriazole  content  by Gas  Chromatography  and  H$_{3}$ P0$_{3 }$ content  by Ion  Chromatography.  The  H$_{3}$P0$_{3 }$ was found  to be  completely  transferred  into  the  aqueous  layer.  Complete  return  of  benzotriazole  to the  butyraldehyde  layer  was  also  found.  The  procedure  for  Example  2  was  repeated  with  the  modification  of  adding  0.017grams  of  phosphorous  acid  (Hi’O 3 )  to the  12  gram  solution.  After  24  hours  the con› centration  of  Ligand  D had  decreased  from  0.39  to  0.12  percent  by  weight;  after  72  hours  the  concentration  of  Ligand  D had  decreased  to  0.04  percent  by  weight.  This  data  shows  that  strong  acids  catalyze  the  decomposition  of  Ligand  D.  This  Example  is  similar  to  Example  2  except  that  phos› phorus  acid  was  added  to  simulate  the type  of acid  that might  be  formed  during  hydrolysis  of an  organophosphite.  This  example  shows  that  a  buffer  solution  is  effective  at  neutralizing  an  organic  soluble  salt  of a  weak  base  and  strong  acid  thus  allowing  the base  to  return  to the  organic  phase  and  effectively  removing  the acid  from  the  organic  phase.  To a  clean,  dry  25  milliliter  vial  was  added  12  grams  of  the  butyraldehyde  solution  mentioned  above.  Samples  were  analyzed  for  Ligand  D  using  High  Performance  Liquid  Chromatography  after  24  and  72  hours.  The  weight  percent  of  Ligand  D  was  determined  by  High  Performance  Liquid  Chromatography  relative  to a  calibration  curve.  No  change  in the  concentration  of  Ligand  D  was  observed  after  either  24  or 72  hours.  This  control  example  illustrates  the  stability  of  Ligand  D  (as  identified  herein)  in a  solution  containing  200  parts  per  million  of  rhodium,  and 0.39  percent  by  weight  of  Ligand  D  in  butyraldehyde  containing  aldehyde  dimer  and  trimer  in  the  absence  of  added  acid  or  benzimidazole.  This  data  shows  that  an  organic  soluble  nitrogen  base  which  exists  as a  strong  acid  salt  can  be  regenerated  by  contact  with  an  aqueous  buffer  and  returned  to the  organic  phase.  Examples  2 to  6  illustrate  the in  situ  buffering  effect  of  nitrogen  containing  additives  such  as  benzimidazole  and the  ability  of  these  additives  to  transfer  the  acidity  to an  aqueous  buffer  solution.  Solid  (benzimidazole)(H$_{3}$ P0$_{4}$ )  was  prepared  by  placing  1.18  grams  ( 10  mmole)  of  benzimidazole  in a  250  milliliter  beaker  and  dissolving  the  benzimidazole  in 30  milliliters  of  tetrahydrofuran.  To this  solution  was  slowly  added  0.5  grams  of  86  percent  by  weight  of  phosphoric  acid  (H$_{3}$ P0$_{4}$ ).  Upon  addition  of the  acid  a  precipitate  formed.  The  precipi› tate  was  collected  on a  sintered  glass  frit and  washed  with  tetrahydrofuran.  The  resulting  solid  was  air-dried  with  the  application  of  vacuum  and  used  without  any  further  purifi› cation.  0.109  grams  (0.504  mmole)  of the  water-soluble  (benzimidazole)(H$_{3}$ P0$_{4}$ )  solid  prepared  in the  previous  step  was  dissolved  in 10  grams  of  0.lM  pH  7  sodium  phosphate  buffer  solution.  The  resulting  solution  was  extracted  with  10  grams  of  valeraldehyde.  The  organic  layer  was  then  sepa› rated  from  the  aqueous  layer  using  a  separatory  funnel.  The  volatile  components  were  then  removed  from  the  organic  layer  by  distillation  at  100°  C.  to  yield  a  solid.  The  solid  was  identical  to  authentic  benzimidazole  as  shown  by thin  layer  chromatography  utilizing  a  1: 1  by  volume  mixture  of chlo› roform  and  acetone  as the  eluent  and silica  as the  stationary  phase.  Based  on  recovery  of the  solid.  benzimidazole  was  completely  transferred  to the  organic  phase.  This  example  shows  that  an  aqueous  buffer  can  recover  the  acidity  from  the  nitrogen  base  in situ  buffer  and allow  the  nitrogen  base  to  partition  into  the  organic  phase,  where  it can  be  recycled  to the  hydroformylation  zone.  The  procedure  for  Example  2  was  repeated  with  the  modification  of  adding  0.018  grams  of  phosphorous  acid  and  0.0337  grams  of  benzimidazole  to the  solution.  No  decom› position  of  Ligand  D  was  observed  after  either  24 or  72  hours.  This  shows  that  the  addition  of  benzimidazole  effec› tively  buffers  the  effect  of the  strong  acid  and  thereby  prevents  the  rapid  decomposition  of  Ligand  D.  This  Example  is  similar  to  Example  2  except  that  both  phosphorus  acid  and  benzimidazole  were  added.  from  undergoing  extreme  cycling  during  the  operation  of the  reactor  system.  The  feed  rate  of the  olefin  to the  system  is  224.4  grams  per hour  per liter  of  reaction  volume.  Table  B  summarizes  results  for  several  different  feed  compositions  for  temperature  differences  between  the  reaction  and  the  temperature  of the  coolant  entering  the heat  transfer  means  that  prevent  the  system  from  undergoing  extreme  cycling.  Factor  for  the  ReactiviJI  of  Ljgan::I  F at  Various  Conditions  Temperatures.  deg  C.  Rh,  ppm  25  45  60  100  120  10  O.Dl  O.Q3  0.08  0.53  1.19  30  0.03  0.10  0.24  1.59  3.57  60  0.06  0.20  0.47  3.18  7.14  100  0.10  0.34  0.78  5.30  11.90  150  0.15  0.51  1.18  7.94  17.84  200  0.19  0.68  1.57  10.59  23.79  250  0.24  0.85  1.96  13.24  ’19.14  300  0.29  1.02  2.35  15.89  35.69  Summary  of  Temperature  Differences  to  Eliminate  Cycling  Reactiv  ity  Factor  2.6  1.13  1.40  Propylene  Conversion,  %  75  60  65  Syn  Gas  Feed,  g/hr/L  171  133  138  Hydrogen  to  Carbon  Monoxide  Ratio  1:1  0.85  0.85  Temperature  Difference,  degC.  7  13  24 