Page 131 - Principles of Catalyst Development
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CATALYST  PREPARATION                                           119


                                                                   0
                                           0
                       5           15 hrs, 400 C   REDUCED  15hrs  AT  500 C
                                   82%  REDUCED   17wt%  Ni/SiO z ,93% REDUCED
                                                               2
                                                       Scale  =142  m 9 Ni- I
                                                       SUP = 78  m:! 9  Ni- I
                       4
                N(rl
                       .3

                       .2


                       .1


                        0         2    3    4    o         2    3   4    5

                                      CRYSTALLITE  RADIUS  ,nm
                 Figure 6.21.  Effect of reduction temperature on crystallite size  distribution. I \7R)









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                              2  3  4  0      2  3  4   0    234
                                           RADIUS, nm
           Figure  6.22.  Effect  of  hydrogen  velocity  on  the  extent  of  reduction  for  25%  Ni/Si0 2  at
           4000C ,1I7B)
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