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
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