Page 154 - Modeling of Chemical Kinetics and Reactor Design
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124    Modeling of Chemical Kinetics and Reactor Design

                                Rearranging Equation 3-50 and integrating between the limits yields


                                 C A  −dC     t
                                  ∫    2  A  = kdt                                       (3-51)
                                              ∫
                                 C AO  C A    0


                                  C A
                                   1 
                                     =  kt
                                  C A                                                  (3-52)
                                 C AO

                                  1     1
                                     −      =  kt
                                 C A   C AO                                              (3-53)


                              or

                                  1    1
                                    =     +  kt
                                 C A  C AO                                               (3-54)


                                In terms of the fractional conversion, X , Equation 3-50 becomes
                                                                      A
                                 C AO  dX A  = kC (1 − X ) 2
                                              2
                                    dt        AO      A                                  (3-55)


                                Rearranging Equation 3-55 and integrating gives


                                 X A  dX            t
                                 ∫      A  2  =  kC AO ∫  dt                             (3-56)
                                         A
                                 0  ( 1− X )        0
                                Equation 3-56 yields


                                       1   
                                 X A
                                    (       =  kC AO t                                 (3-57)
                                  0   1 X−  A ) 

                                Equation 3-57 gives
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