The  Phenomena  of  Catalysis. 
f  Am.  Jour.  Pharrn. 
\  November,  1913. 
It  may  be  that  all  cases  of  catalysis  are  to  be  looked  at  as  brought 
about  either  by  the  formation  of  intermediate  chemical  compounds 
of  the  catalyzer  with  one  or  both  o'f  the  reagents  and  the  subsequent 
breaking  down  of  such  compounds  to  the  final  reaction  products,  or 
of  physical  adsorptions  corresponding  to  the  increasing  of  concen- 
tration of  one  or  more  of  the  reacting  substances. 
The  chemical  industries  are  full  of  the  most  interesting  and 
successful  catalyses.  Sulphuric  acid  manufacture  has  always  made 
-  use  of  catalyzers  in  some  form.  In  the  early  days  it  was  the  nitrogen 
oxides,  and  now  it  is  platinum  sponge,  etc.  When  sulphur  is  burned 
in  air,  or  oxygen,  the  dioxide  is  produced,  and  this,  even  in  the 
presence  of  excess  of  oxygen,  does  not  seem  inclined  to  continue 
in  the  process  of  oxidation  to  the  state  of  trioxide  at  any  measurable 
rate.  Yet  this  is  the  direction  it  should  proceed,  and  any  one  of 
several  triggers  or  catalyzers  will  effect  it.  It  is  very  important  to 
note  that  the  final  state  of  all  of  these  catalyzed  reactions  is  the 
"  natural  "  state ;  that  is,  no  consumption  of  energy  is  needed  to 
reach  the  state,  and  energy  is  evolved  by  the  process.  The  sulphur, 
in  burning,  tends  to  become  the  trioxide.  Under  normal  conditions 
it  only  reaches  the  dioxide  state  in  measurable  time,  but  contact 
with  such  a  solid  as  platinum  sponge  will  catalyze  the  reaction,  thus 
producing  with  great  rapidity  sulphur  trioxide  (the  anhydride  of 
sulphuric  acid). 
The  great  German  dye  firm,  the  Badische  Analin  u.  Soda  Fabrik, 
made  careful  study  of  catalyzers  for  the  reaction  between  hydrogen 
and  nitrogen  by  which  they  hoped  to  and  finally  did  make  ammonia 
commercially.  The  reaction  was  a  perfectly  possible  one,  but  with- 
out catalysis  it  was  always  too  slow  to  be  practical.  Finely  divided 
iron,  manganese,  molybdenum,  and  tungsten  were  all  found  to  be 
effective,  and  it  was  further  found  that  these  catalyzers  could  easily 
be  poisoned  by  some  reagents,  but  could  be  benefited  by  others. 
Thus  arose  the  term  "promoters  "  in  catalyzers.  A  small  quantity 
of  some  substance,  such  as  an  oxide,  for  example,  serves  as  a  pro- 
moter to  the  catalytic  action  of  iron  on  the  ammonia  synthesis. 
Thus  a  practical  and  commercial  process  for  direct  synthesis  of 
ammonia  has  been  brought  about.  This  reminds  one  somewhat 
of  the  complements  and  the  immune  bodies  which,  while  co- 
operating in  the  blood,  produce  the  effects  of  immunity. 
There  seems  to  me  to  be  one  simple  way  of  looking  at  all  cata- 
lyzers which  is  useful  if  it  be  not  used  unfairly.    The  velocity  of 
