Page 206 - Elements of Chemical Reaction Engineering 3rd Edition

178 lgothermal Reactor Design Chap. 4

Po T
Stoichiometry u = FT 7; (3-41)

to give the case of an ideal g8s (Z = 1). We now recall Equation (3-451,

(3-45)

The total malar flow rate is given as the sum of the flow rates of the individual
species:
n
F, = J-1 c Fj

when species A, B, C, D, and I are the only ones present. Then
F, = FA+ F, + Fc + F,+ F,

The molar flow rates for each species FJ are obtained from a mole balance on
each species, as given in Table 4-6: for example,
ti
Must write a dF
I=
mole balance on dV (4-42)
each species
We now return to Example 3-8 to complete its solution.

TABLE 4-6 ALGORITHM FOR GAS-PHASE REACTIQNS
aA+bB + cC+dD
1. Mole balances:
Batch CSTR PFR

-- dF, = rA
‘2 - r,V
dV

- -
dFc -
dV I C

2. Rate Law:
-rA = kAC2Ci
3. Stoichiometry:
Relative rates of rciCtIOn:
rA =__ -%=2
‘B
c
-a -b c d