Page 493 - Elements of Chemical Reaction Engineering Ebook

464 Steady-State Nonisothermal Reactor Design Chap. 8

Because only A enters,
EO, cpi = cp,

and Equation (E8-7.7) becomes

dT
-
dV
Adiabatic PFR 6. Calculation of mole balance parameters:
with variable heat
capacities kg/h = 137.9 kmol/h = 38.3 mol/s
= 58 g/mol
CA, = - 162 Ha = 0.0188 - 18.8 m0l/m3
kmol -
‘A0
=
-
RT m3
8.3 1 (1035 K)
hol* K
FAO -
uo = - - 2.037 m3/s
CAO
7. Calculation of energy balance parameters:
a. AHix (TR): At 298 K, the standard heats of formation are
H;x(TR)acetone -216.67 kJ/mol
=
Hix(TR)ketene -61.09 kJ/mol
=
Hix(TR)me*me = -74.81 kJ/mol
AHiX(TR) = (-61.09) + (-74.81) - -216.67)
(
= 80.77 kJ/mol
b. ACp: The heat capacities are:
CH3COCH3: C,, = 26.63 + 0.1837‘- 45.86 X 10-6T2 J/mol..K
CH,CO: C,, = 20.04 + 0.0945T - 30.95 X T2 J/mol* K
CH, : Cpc = 13.39+0.077T- 18.71 x 10-6T2 J/mol-K

Aa = aC + a, - aA = 13.39 + 20.04 - 26.63
= 6.8 J/mol-K
AP = Pc + PB - PA = 0.077 + 0,0945 - 0.1 83
= -0.0115 J/mol.K2
Ay = yc+yB-yA = (-18.71 X 10-6)+(-30.95X 10-6)-(-45.86X

= - 3.8 X J/mol. K3