11.  3,251,895  12  Catalyst  preparation  (A).-In  a  typical catalyst  prepa› ration, an  oxy-compound,  for  example,  sodium metasili› cate, having  a  particle sizing  in the range  1~10 microns  and  practically  freed of  adsorbed  extraneous  matter,  is  dispersed  in an  aprotic  hydrocarbon  medium,  such as an  alkane,  cycloalkane,  and a  paraffinic  petroleum  fraction  practically  freed • of  aromatic  hydrocarbon  and  partially  oxidized  hydrocarbon  impurities.  Even where  1-10  microns  presized  solid particles  are used,  it  is  frequently  desirable  to  subject the  solid admixed  with the  paraffinic  hydrocarbon  (weight ratio  hydrocarbon  to solid  about  85-15)  to a period  of  ball-milling  or the  equivalent.  Where presized  particles  of the  desired  . solid oxy› compound  are not  available,  the  powdered  solid may  be  subjected  as above  to  milling  in the  presence  of the par~  affinic  hydrocarbon  in a ball,  paint, or  colloid mill  until  (B)  In a second  ally!  alkylation  catalyst  preparation,  232 grams  of  crystalline  metamorphic  magnesium,  cal› cium, and  aluminum  silicate were  ball-milled  in the  presence  of 1,318  grams of  refined white  oil until  micro› scopic  inspections  of  samples indicated  the  particle sizing  was in the  1-10 micron  range.  The mixture  was then  transferred  to a  5  liter stainless  steel flask  equipped  with  a high speed  stirrer and  the  mixture diluted  to 3.3 liters  by the  addition  of white  oil.  Under an  atmosphere  of  nitrogen  the  mixture was  •heated  to 120°  C. for one  half- hour, at  which time  while  •  stirring at•  high. speeds  225  grams of  potassium  were added  in three  increments  with  about  5  minute intervals  between  the  additions  and with  a 30  minute  continuation  after the  last  addition.  One› half liter  of white  oil  containing  4.6 grams  of oleic acid  was then  added in  two  increments  into the  slurry and  the  mixture  was stirred  for an  additional  30  minutes.  The particles  were found  to be in  the 2-15  micron size  range.  A  further addition  of 5.3 grams  of oleic  acid in  .25 liter  of oil were  made, and  the  maximum  particle  size found  was  7  microns.  A 200 gram  aliquot  of the  slurry was  transferred  -to a 500  cc.  three-necked  flask  fitted with  a  stirrer, and  the flask  and contents  were  heated  to  210°  C. under  an  atmosphere  of  nitrogen.  The  nitrogen  atmosphere  was  replaced  with  hydrogen  and  the  system was  held at  210-220°  C. for 35  minutes.  The catalyst  thus  prepared  was cooled  to 130°  C. under  an  atmosphere  of  hydrogen,  and then  to room  tempera› ture under  an  atmosphere  of  nitrogen.  The  maximum  particle  size was  3  microns.  Titration  of the  aliquot  was  2-methoxy  ethanol indicated  146% of  the  theoretical  hydrogen  expected  for  potassium,  showing  the  presence  of  potassium  hydride.  This catalyst  when tested  in use,  for  example,  to  catalyze  the  dimerization  of  propene  at  150°  C. and a  pressure  of 1200  p.s.i.g. required  no in- duction period  and had  an  exceptional  catalytic  activity.  Inspections  of the used  catalyst indicated  the  particle size  to be less  than 6 microns  in size. When  the hydride  allyl  alkylation  catalyst was  prepared  in an  analogous  man› _ner, except  that the  oxy-compound  and polar  organic  compound  were omitted,  inspection  indicated  that the  These data  indicate that  while at  least about  8-10 cc.  of a mixed  crystalline  metamorphic  silicate  is  required  to yield a  stable catalyst,  as much  as 41 cc.  of the super› finely divided  solid is  an excess.  No  particular  disad› vantage  was noted  by reason  of the excess  in this test.  In a  continuous  unit,  however,  unneeded  oxy-compound  detracts  from the  reactor unit  volume• production  effi› ciency.  When other  unreactive  superfinely  divided oxy› compounds  are used,  similar results  obtained,  although  minor variations  in  relative amounts  may be  desirabie.  On  the other  hand, when  the  oxy-compound  used has  a  particle size  less than  about 0.1  micron, i.e.,  a  material  having  a size  ‰o  and less  of the alkali  metal particles  normally  attainable,  no stable  complex  results.  Thus,  when for  each gram  atom of  alkali metal  about 13.4  cc.  of  calcium phosphate  ha:ving an  estimated  particle size  of  0.03 micron  was  substituted,  the  potassium  agglomerated  and no allyl  alkylation  catalyst  complex  was  obtained.  Ally!  alkylation  catalysts  prepared  in this  manner  are  highly  reproducible,  are stable  to  temperature  fluctua› tions under  ally!  alkylation  conditions,  and  consistently  have  reactivities  at least 50  to 100%  higher than  the ally!  alkylation  catalysts  known  in the art.  Representative  catalysts  thus  prepared  have  produced  from  1500-2000  kilograms  of  propene  dimer per  kilogram  of  potassium  used to prepare  the  catalyst  up to the  termination  of the  experimental  run for reasons  other than  catalyst deactiva› tion.  In the  preferred  manner,  a series of  catalysts  was pre› pared and  tested, as  in  Example  2, using  10 parts  solid  (alkali metal  plus  oxy-compound,  Ca, Mg,  Al  silicate),  90 parts  of  refined paraffin  white oil,  and oleic  acid in  the  proportions  listed in  Table  V  following.  The  dispersion  is th.en  heated  to a  temperature  above  the  melting point  of the alkali  metal to  be used and  pref› erably to  100-120°  C.  and the alkali  metal and  the polar  organic compound  are  introduced  into the slurry  and con- tacted, while  high speed  stirring  or the like  is  continued.  For the  preparation  of the more  concentrated  catalyst3  incremental  addition  is  usually made.  The  dispersing  action  is  continued  at  temperature  for a period  sufficient  to  facilitate  even  distribution  of the  catalyst components  and some  conditioning  of the  associated  complex.  A pe› riod of about  0.5 to 1 hour  usually  is  adequate;  however,  a  positive  determination  is  possible  by  inspection  of a  sample under  the  microscope.  Particle sizes  should  be  less than  about 15  microns.  The weight  ratio of  dispersed  solid in paraffin  is ad› justed in  accordance  with the  catalyst  concentration  desired  by adding  adq.itional  hydrocarbon  after transfer  of ,the  solid-oil  dispersion  to a  suitable vessel  fitted with  an  efficient dispersing  means such  as an ultra  high speed  (10,000-15,000  r.p.m.) high  shear blade  fitted stirring  mechanical  element,  an  ultrasonic  vibrator  or the equiva- lent.  inspection  under high  powered  microscope  indicates  the  particles  are  properly  sized.  EXAMPLE  6  EXAMPLE  7  Table V  CC. of Solid/  Mols Polar  Gram Atom  Organic  gC,H,/gK  Catalyst  Potassium  Compound/  Dimerized/  Inspection  (1-10  microns)  Gram Atom  Hour  KXlO  6. 7  ---------------- 2.8  0.0  Agglomerated.  13.4 ___ ----- ----___  2.8  5.4  Stable Complex.  26.8  _______________  5.6  5. 7  Do.  40.6 ____ ---- ------- 2.8  -------------- Much  Uncomplexed  Oxy-Compound.  Catalyst Active  and  Stable.  process.  Two catalysts  were  prepared  under  comparable  conditions  except that  the  oxy-ccimpound,  a  silicate  in  one  instance,  contained  possibly  as much  as  5  % of 20+  micron particles,  and in the  other the  same material  was  subjected  to  comminution  such ,that  the  particles  were  essentially  all in the  range 1-10  microns.  In the prepa› ration of  the  catalyst  the  components  were present  in the  proportions  of 1 gram  atom of  potassium,  13.4 cc. of  the  silicate, and  5.4  Xl0- 3  mols of  oleic acid.  Each cata› lyst was  tested as  in  Example  2 and then  inspected.  The  catalyst  prepared  from the  1-10 micron  sized silicate  was  especially  suited for  use in a  continuous  reactor; the  other had  agglomerated  to • a hard  unreactive  solid.  These and  similar data  indicate  that for  the  preparation  of sta:ble  superfinely  divided alkali  metal  containing  ally!  alkylation  catalysts,  not only  must an  unreactive  solid  compound  be used,  but it must  ,be  of a  particle size  com› parable  to that of  the active  component. 