Page 99 - Modeling of Chemical Kinetics and Reactor Design

Thermodynamics of Chemical Reactions 69

Thus,

c
o
f • f D d = K = exp   − ∆ G  (2-48)
C

a
f • f b f  RT 
A B
Replacing f by φ p gives
i i
i
c
c
φ • φ d p • p d
C D • C D = K
a
a
φ • φ b B p • p b B f (2-49)
A
A
Since p = yP, Equation 2-49 then becomes
c
c
φ • φ d D • y • y d D = KP ( ab c d)
+− −
C
C
a
a
b
φ • φ b B y • y B f (2-50)
A
A
Fugacities are evaluated at the conditions at which the gases exist
in the mixture.
LIQUID STATE
Chemical potentials can be expressed as:
*
µ = µ + RT ln γ x (2-51)
i i i i
or
*
µ = µ + RT ln a i (2-52)
i
i
where x = mole fraction of component i
i
γ = activity coefficient of component i
i
a = activity of component i
i
Equation 2-52 gives

c
a • a d D = exp   −∆µ *  K
 =
C
a
a • a b  RT  L (2-53)
A B