35  5,744,649  36  In  a  preferred  embodiment  of  this  invention,  one  or  more  aldehyde  products  removed  by  water  extraction  can  be  recovered  and  returned  to  the  hydroform.ylation  process  as  depicted  in  the  process  flow  diagram  of  FIG.  1.  For  example,  The  contacted  water  employable  in  this  invention  may  comprise  any  suitable  water  such  that  the  pH  of  the  con- tacted  water  may  range  from  about  2 to  about  7.5,  preferably  from  about  2.5  to  about  7  and  more  preferably  from  about  3 to  about  6.  The  flowrate  of  water  through  the  extractor  and/or  the  addition  of  water  to  the  at  least  one  reaction  zone  and/or  the  at  least  one  separation  zone  should  be  sufficient  to  control  pH  of  the  water  at  desired  levels.  An  increased  flowrate  of  water  through  the  extractor  may  cause  removal,  i.e.,  through  the  water  effluent.  of  certain  amounts  of  one  or  more  aldehyde  products  from  the  process.  Internal  techniques  where  additives  are  used  to  counteract  the  harmful  e:tfects  of  impurities  can  also  be  used  to  prepare  non-contacted  water  for  use  in  extraction,  but  the  external  techniques  described  in  the  preceding  paragraph  are  more  preferred.  For  purposes  of  this  invention,  "non-contacted  water"  is  contemplated  to  include  water  that  has  not  been  contacted  The  preferred  method  of  operation  of  this  invention  is  to  pass  all  or  a  portion  of  the  reaction  product  fluid  before  aldehyde  removal  or  reaction  product  fluid  concentration  after  removal  of  aldehyde  through  the  water.  Alternately,  water  may  be  sprayed  into  or  otherwise  added  to  the  at  least  one  reaction  zone  or  the  at  least  one  separation  zone  to  achieve  acidity  control.  The  water  layer  formed  may  then  be  separated,  e.g.,  decanted,  from  the  reaction  product  fluid.  An  advantage  of  this  scheme  is  that  extraction  capability  is  immediately  available  if  acidity  forms  in  the  reaction  prod› uct  fluid.  This  invention  is  not  intended  to  be  limited  in  any  manner  by  the  permissible  means  for  contacting  a  reaction  product  fluid  with  water  (either  inside  or  outside  of  the  reaction  zone  or  separation  zone).  A  preferred  process  to  purify  non-contacted  water  neces- sary  for  the  acid  removal  would  be  a  combination  of  some  of  the  aforementioned  techniques.  Membranes  separate  based  on  size,  electronic  charge.  hydrophobicity,  or  other  physical-chemical  property  differ› ences.  Reverse  osmosis  is  an  example  of  using  membranes  to  purify  water.  If  dissolved  gases  such  as  oxygen  are  present,  the  water  can  be  stripped  with  steam  or  nitrogen  or  subjected  to  vacuum  to  remove  or  replace  the  dissolved  gas.  Moreover.  success  in  removing  phosphorus  acidic  com› pounds  from  the  reaction  product  fluid  according  to  the  subject  invention  may  be  determined  by  measuring  the  rate  degradation  (consumption)  of  the  organophosphite  ligand  present  in  the  hydroform.ylation  reaction  medium.  The  con› sumption  rate  can  vary  over  a  wide  range,  e.g..  from  about;§0.6  up  to  about  5  grams  per  liter  per  day.  and  will  be  governed  by  the  best  compromise  between  cost  of  ligand  and  treatment  frequency  to  keep  hydrolysis  below  autocata› lytic  levels.  Preferably  the  water  treatment  of  this  invention  is  carried  out  in  such  a  manner  that  the  consumption  of  the  desired  organophosphite  ligand  present  in  the  hydroform.y› lation  reaction  medium  of  the  hydroform.ylation  process  is  maintained  at  an  acceptable  rate,  e.g.,;§0.5  grams  of  ligand  per  liter  per  day,  and  more  preferably~0.1  grams  of  ligand  per  liter  per  day.  and  most  preferably~0.06  grams  of  ligand  per  liter  per  day.  As  the  extraction  of  phosphorus  acidic  compounds  into  the  water  proceeds.  the  pH  of  the  water  will  decrease  and  become  more  and  more  acidic.  When  the  water  reaches  an  unacceptable  acidity  level  it  may  simply  be  replaced  with  new  water.  Water  treatment  should  begin  with  an  evaluation  of  the  water  quality  needs  for  the  process.  For  acid  extraction  from  reaction  product  fluids  containing  metal-organophosphite  ligand  complex  catalysts.  the  quality  of  water  required  is  generally  of  boiler  quality  or  better.  Sources  of  water  for  purification  can  vary  greatly  in  purity  from  river  water  containing  logs.  silt  and  other  debris,  to  steam  condensate  that  is  relatively  pure.  If  river  water  is  to  be  used,  purifica› tion  starts  with  filtration  of  the  largest  pieces.  Grates  or  screens  may  be  used  for  this  first  filtration  step.  A  number  of  techniques  can  be  used  to  remove  other  solids  that  may  be  present  in  the  water  including;  sedimentation,  centrifugal  separation,  filtration.  coagulation.  flocculation.  magnetic  separation.  of  combinations  of  these.  After  clarified  water  is  obtained.  the  remaining  dissolved  solids  can  also  be  treated  in  a  number  of  ways.  Distillation  is  still  commonly  prac› ticed.  Dissolved  salts  may  be  treated  with  other  acids  or  bases  to  precipitate  certain  compounds.  The  acids  or  bases  that  are  added  are  chosen  based  on  the  solubility  of  the  compounds  that  will  be  produced.  Ion  exchange  is  another  popular  method  for  removing  dissolved  salts.  The  most  common  ion  exchange  method  uses  sodium  as  the  cation.  Other  ion  exchange  techniques  with  protons  or  hydroxide  ions  may  also  be  employed.  Adsorption  can  be  used  to  remove  some  metal  salts  and  organic  compounds  that  may  be  present.  Activated  carbon  is  used  commonly  as  an  adsor› bent.  Membranes  are  still  another  technique  that  may  be  used  removed  dissolved  salts  or  other  colloidal  particles.  For  instance,  a  preferred  quantity  of  water  is  the  quantity  which  ensures  that  any  degradation  of  the  organophosphite  ligand  proceeds  by  the  "non-catalytic  mechanism"  as  described  in  "The  Kinetic  Rate  Law  for  Autocatalytic  Reac› tions"  by  Mata-Perez  et  al  ..  Journal  of  Chemical  Education.  Vol.  64.  No.  11.  November  1987,  pages  925  to  927.  rather  than  by  the  "catalytic  mechanism"  described  in  said  article.  Typically  maximum  water  concentrations  are  only  governed  by  practical  considerations.  As  noted.  treatment  conditions  such  as  temperature,  pressure  and  contact  time  may  also  vary  greatly  and  any  suitable  combination  of  such  conditions  may  be  employed  herein.  For  instance.  a  decrease  in  one  of  such  conditions  may  be  compensated  for  by  an  increase  in  one  or  both  of  the  other  conditions.  while  the  opposite  correlation  is  also  true.  In  general  liquid  temperatures  rang› ing  from  about  10°  C.  to  about  120°  C ..  preferably  from  about  20°  C.  to  about  80°  C..  and  more  preferably  from  about  25  °  C.  to  about  60°  C.  should  be  suitable  for  most  instances,  although  lower  or  higher  temperatures  could  be  employed  if  desired.  As  noted  above.  it  has  been  surprisingly  discovered  that  minimum  loss  of  organophosphite  ligand  occurs  when  $_{a }$hydroformylation  reaction  product  fluid  con› taining  $_{a }$metal-organophosphite  ligand  complex  catalyst  is  contacted  with  water  even  at  elevated  temperatures.  Nor› mally  the  treatment  is  carried  out  under  pressures  ranging  from  ambient  to  reaction  pressures  and  the  contact  time  may  vary  from  a  matter  of  seconds  or  minutes  to  a  few  hours  or  more.  Any  means  to  prepare  the  non-contacted  water  for  use  with  the  process  of  this  invention  can  be  used  so  long  as  the  water  is  substantially  free  of  catalyst  poisons,  inhibitors,  or  compounds  that  would  promote  undesirable  side  reactions  in  the  catalyst  solution.  A  summary  of  water  treatment  tech› niques  can  be  found  in  the  Kirk  Othmer,  Encyclopedia  of  Chemical  Technology.  Fourth  Edition.  1996.  with  the  reaction  product  fluid  and  "contacted  water"  is  contemplated  to  include  water  that  has  been  contacted  with  the  reaction  product  fluid.  sufficient  to  at  least  maintain  the  concentration  of  such  acidic  compounds  below  the  threshold  level  that  causes  rapid  degradation  of  the  organophosphite  ligand. 