Page 245 - Modeling of Chemical Kinetics and Reactor Design

Reaction Rate Expression 215

and

K = k 1 = C 2 HS
1 2 (3-342)
k − 1 p H 2 C S

3
S
K = k 3 = CC NH S (3-343)
3
3
k − 3 C NS C 3 HS

K = k 4 = Cp
SNH 3
4
k − 4 C NH S (3-344)
3
From Equation 3-343, the concentration of the most abundant
surface intermediate is

3
CC HN S
s
C NS = 3 (3-345)
KC 3
3 HS
The concentration of adsorbed ammonia from Equation 3-344 is

Cp
C = SNH 3
NH S K 4 (3-346)
3

The concentration of adsorbed hydrogen from Equation 3-342 is

HS ( S) 12
2
C = K p H 2 C (3-347)
1
Substituting Equations 3-346 and 3-347 into Equation 3-345 gives

3
CC p
S
C NS = S NH 3 32 (3-348)
(
2
KK K p H 2 C S)
1
3
4
p C S
= NH 3 (3-349)
.
Kp 15
H 2