Page 136 - Principles of Catalyst Development
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124                                                      CHAPTER  6
            moves to  pilot unit testing  or commercial  demonstration  stages, then  tens
            or  even  hundreds  of  kilograms  are  required.  Commercialization  may
           demand plant capacities approaching hundreds of thousands of kilograms
            per  year.  Commercial  catalysts  must  not  only  faithfully  reproduce  the
            performance  of laboratory  preparations  but  must  also  be  uniform,  con-
           sistent,  and  economical.  A  typical  production  line  is  shown  in  Fig.  6.24.
            Exact  configurations vary  from  one  product to  another but  follow  similar
            routes.
                Although  catalyst  manufacturing  follows  the  same  procedures  as
           laboratory  preparations,  scale-up  to  marketable  products  introduces  con-
           siderations not encountered in small-scale operations. (182)

           6.7.1.  Duplication  and  Scale-Up of Laboratory  Recipes

                During the course of normal catalyst development, a successful recipe
           is  finalized  and  negotiations opened with  a  manufacturer to move to  pilot
           testing  and  possible  commercialization.  Before  serious  talks  proceed,  the
           manufacturer  will  insist  on  testing  the  reproducibility  of the  recipe  and
           attempt  to  make  the  catalyst  from  the  laboratory  instructions.  This  is  to
           ensure that critical factors are understood and are not unknown artifacts of
           specific  conditions.  As  strange  as  it  may  seem,  cases  are  known  where
           atmospheric dust in  the  laboratory was  a  key  ingredient to  nucleation of a
           gel  and other environments did  not work. This emphasizes the importance
           of keeping complete records during the research stages, not only for patent
           reasons but also as a source for tracing irregularities. Once the manufacturer
           satisfies  himself that  the  recipe  is  accurate,  then  he  can  proceed  with  the
           question of scale-up.
                     m. m


                                         FIL TER
                                                  DRIER  &
                     y\{  ~ .~ ......  CALCINER                MIXED  OXIDES
                       ~~.  ~.----------------                 &  CARBONATES
                               .<r..J   PRECIPITA TION   (0   oj"
                 MIXED    SODIUM    &  AGEING               :
                 METAL    CARBONATE   VESSEL
                 NITRATES   TANK
                 TANK                    FEED
                                         POWDER                   GRAPHITE
                                         MIXER                   WEIGHING
                                         BIN                     MACHINES
                            PARTIAL
                           REDUCTION  FINISHED
                         ___ IN  __ •·   ..,-
                CATALYST
                           REACTOR  PELLETS  PELLETTING
                                            MACHINE
                      Figure 6.24.  Typical  production  line  for  catalyst  manufacturing.
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