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.