Page 58 - Principles of Catalyst Development
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CATALYST DEVELOPMENT 45
extremely useful. Utilization rather than analysis is often more fruitful;
success its own reward. It is not surprising that commercial solutions in
catalysis almost always outdistance scientific understanding. And yet it is
only through the pursuit of precise and accurate models that we advance
one more step and facilitate success in future endeavors. The research phase
ultimately reaches a stage where expediency or financial limitations dictate
that the next step be taken with the information at hand. The better prepared
we are to interpret this information, the more successful will be our designs.
3.5. CATALYST DESIGN
Catalyst design involves selecting candidates for further testing and
optimization. These may be very close to the final form ifbased on previously
proven catalysts. For novel designs, however, considerable adjustment lies
ahead.
To the uninitiated, designing a catalyst is a mysterious process.
However, familiarization with the chemistry of the process, and especially
the mechanism, narrows the choice of possible materials. By comparison
with similar reactions, by use of correlations and patterns of behavior, and
from current research, it is possible to arrive at fairly good estimates as a
starting point.
Systematic, scientific methods for catalyst design have been pursued
by researchers for many years. A recent book gives many examples(85) and
more details and guidance are found in Chapter 5.
Candidate catalysts from the design may be new or novel compositions,
giving the designer a proprietary position. However, commercialization
takes longer since there are many steps remaining before the worthiness of
the invention is demonstrated. To solve an immediate process problem, the
best solution is a design already proven or commercialized. Having survived
manufacturing scale-up and implementation, such a catalyst is much more
readily available for dependable testing.
Another possibility is a development catalyst. These are catalysts,
usually under development by catalyst manufacturers, that are not fully
commercialized. All manufacturers have many available. It is worthwhile
to consider these sources since subsequent steps are accelerated.
After the design phase, exploratory catalysts are made for testing.
Although small-scale preparations using colloidal laboratory procedures
are used, careful records should be maintained. This not only protects patent
claims but aids future reproduction and scale-up by manufacturers.
An important feature at this stage is optimization of critical properties.
Design only specifies active components, supports, and promoters. It does