Page 538 - Elements of Chemical Reaction Engineering Ebook

508 Steady-State Nonisothermal Reactor Design Chap. 8

2. The standard heat of reaction per mole of A at reference temperature
TR is given in terms of the heats of formation of each species:
C d b
AH&(TR) = -Hz(TR) f -Hg(TR) - ;Hg (TR) - Hi (TR) (S8-2)
a a
3. The mean heat capacity difference, Atp, per mole of A is

(S8-3)

where kpi is the mean heat capacity-of species i between temperatures
TR and T, not to be confused with Cpj, which is the mean heat capac-
ity of species i between temperatures To and T.
4. When there are no phase changes, the heat of reaction at temperature
Tis related to the standard reference heat of reaction by

AHR,(T) = Hi,(TR) + Aep(T-TR) (S8-4)

5. Neglecting changes in potential energy, kinetic energy, and viscous
dissipation, the steady-state energy balance is

2 - -!% - X[AHi,(T,) + Atp(T- T,)] = f: Oiepi(T- Tio)
FAO FAO i= 1
(S8-5)
where IZ is the number of species entering the reactor.
If all species enter at the same temperature, Tjo = To, and no work is
done on the system, the energy balance reduces to

For adiabatic operation of a PFR, PBR, CSTR, or batch reactor

X[-AH;;,(T,)]+CO~~~~T~+X A~~T,
T=
[E Oi e,, + X Akp]
6. The energy balance on a PFR/PBR

(S8-7)

In terms of conversion

(S8-8)