Page 105 - Principles of Catalyst Development
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92                                                       CHAPTER  5
            5.3.  COMPUTER  AIDS

                Knowledgeable  readers  will  have  no  doubt  perceived  that  this  pro-
            cedure  has  two  obvious  faults.  A  critical  point  in  the  analysis  is  selection
            of the surface mechanism, where the specialized knowledge of the designer
            is  important.  Thus expertise  has  not yet  been  completely eliminated.  One
            individual  may  have  better  success  than  another.  Second,  the  process  of
            writing chemical reactions, calculating thermodynamics, and so on is tedious
            work.  Even  in  the example,  we  restricted  calculations to  one temperature
            for convenience. Third, both the number of reactions and possible mechanis-
            tic paths  appear endless.  Listing of stoichiometric equations, for example,
            is  limited by the patience of the designer.  Many molecular mechanisms are
            feasible, each leading to multiple surface mechanisms, which in turn gener-
            ate a number of candidate catalysts. Although the expertise of the designer
            may help eliminate unlikely possibilities and even assign priorities to others,
            there is  a  danger that impatience, preconceptions, and prejudice may  lead
            to interesting avenues being overlooked.  If the task is  performed properly,
            it is  too time consuming; if not, we  risk loss of possibly successful reaction
            paths through omission. A solution is to use computer-aided catalyst design.
                Modern computers have enormous capacity to store data and perform
           analysis.  Stoichiometric  analysis  and  thermodynamic  interpretation  are
           easily  programmed.  The  range  of reactions  considered  is  thus  expanded.
           Also, correlations and patterns of behavior lend themselves to organization.
            In this way, the accumulated background of many experts is at the disposal
           of the  designer.  Even  the  process  of mechanism generation  is  not  beyond
            computer  capabilities.  As  with  computer-aided  process  design,  many
            possibilities could be developed, priorities assigned, and discrimination left
           to the  human designer,  who,  free  from  manual  tedium, is  now  able  to  let
            his  imagination  and  intuition  roam.  Figure  5.5  shows  the  structure  of the
           computer-aided design. The most effort is  needed in software development
           and data base organization.


           5.4.  SOME  FINAL  THOUGHTS

                Before  the  reader concludes  that  the  catalyst  expert  is  vanishing  and
           that future  inventions  will  come  from  the  uninitiated technologist or even
           computers,  it  should be pointed out that  much  remains to  be done before
           catalysis  is  truly a  science. There is  still  a  need for the alchemist in  us  all.
           But the shrouds of mystery and magic are falling.  The beginner should no
           longer fear to travel  with the  mighty.
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