Page 74 - Principles of Catalyst Development
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CATALYTIC  MATERIALS                                             61

                           1.5                         o


                                                   \
                       oq                     [J
                       o                     o    CYCLOHEXANE
                       ><                       DEHYDROGENATION
                       N
                       [
                       E   1.0
                       ,
                       c:
                       'E
                                   o                  623  K
                       III
                       <II                         CeH'2-0.13  aIm
                       o                           CeHs  -0.065  aIm
                       E          o
                       ui
                       l-
                       e:(
                       cr:  0.5
                       ...J
                       e:(
                       W
                       cr:       CYCLOHEXANE
                       e:(     HYDROGENOL YSIS         i:>
                                 /               6   -BENZENE
                                                   HYDROGENOLYSIS
                            OL-__ ~ ______ -L~~ __ -=L-____ ~
                            1.5   2.0       3.0        4.0       5.0
                                   AVERAGE  RADIUS,  R-V,nm

             Figure 4.12.  Crystallite size  effects  of cyclohexane dehydrogenation/hydrogenolysis.[ [(0)




                                                  TERRACE

















                           Figure 4.13.  Steps  and  kinks  in  crystal  planes.'""
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