Page 71 - Principles of Catalyst Development
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58                                                        CHAPTER  4
                                   V               T9g (X _ y2 )
                          H2                                    2

                                   9 g (z2)           9(z2)
                                                       g

                                ~ ~
                        C 2 H 4

                                   9(z2)          9 g  (z2)  9(Z 2)
                                                           g
                                    g
                                            [ 100)
                                A                          9g(x2-l)
                         H2                      ~
                               9 g (z2)   9 g (z2)







                                            [110 1








                                       NONE  COPLANAR


                   Figure 4.9.  Modes of adsorption  for  hydrogen  and  ethylene on nickel.







                                  TABLE 4.3.  Differences
                                     in  Crystal  Planes
                                  Ammonia Synthesis  11(7)
                                    Plane       Activity

                                    [ 100]        21
                                    [110)
                                    llll]        440
   66   67   68   69   70   71   72   73   74   75   76