Page 130 - Introduction to chemical reaction engineering and kinetics

112 Chapter 5: Complex Systems

5-14 For reaction according to the kinetics scheme

A+B + C+D;% = kicAcB
A + C + 2E; r-E = 2kzcAcc

data are as follows:

Assuming that reaction occurs at constant T in a constant-volume batch reactor, calculate
kl, cc at t, and kg state the units of kl and k2.
5-15 The decomposition of NzOs in the gas phase to N204 and 02 is complicated by the subsequent
decomposition of N204 to NO2 (presence indicated by brown color) in a rapidly established
equilibrium. The reacting system can then be modeled by the kinetics scheme

N205(A)%N204(B) + ;Oz(C)
N204 = Kp 2 N02(D)

Some data obtained in an experiment at 45°C in a constant-volume BR are as follows (Daniels
and Johnston, 1921):

where the partial pressures PA, . . . are also in kPa.
(a) Confirm that the kinetics scheme corresponds to the stoichiometry.
(b) Calculate the values indicated by ?, if Kp = 0.558 bar.
(c) If the decomposition of N205 is first-order, calculate the value of kA.
5-16 The following data (I, in bar) were obtained for the oxidation of methane over a supported
molybdena catalyst in a PFR at a particular T (Mauti, 1994). The products are CO2, HCHO,
and H20.

tlms PCH4 PHCHO PC02
0 0.25 0 0
8 0.249 0.00075 0.00025
12 0.2485 0.00108 0.00042
15 0.248125 0.001219 0.000656
24 0.247 0.00177 0.00123
34 0.24575 0.00221 0.00204
50 0.24375 0.002313 0.003938
100 0.2375 0.00225 0.01025