Page 208 - Elements of Chemical Reaction Engineering 3rd Edition

180 Isothermal Reactor Design Chap. 4

Stoichiometry. Using Equation (3-45) to substitute for the concentrations of A and
B in terms of the molar flow rates, we have for T = To and P = Po gives

(E4-9.4)

(E4-9.5)

where the total molar flow rate, FT, is just the sum of the flow rates of A and B:
FT= FA+FB (E4-9.6)

For every 1 mol of A disappearing 2 mol of B appear:
YB = 2( - m) (E4-9.7)
and

FB = ~(FAo-FA) (E4-9.8)
The total molar flow rate

F, = FA + 2FAO- FA = 2FAo- FA (E4-9.9)
and the total concentration at the entrance to the reactor (Po, To) is calculated from
the equation
Po - 4.1 atm mol
-
CTO z - - dm3. atm (500 K) = 0.1- dm3 (E4-9.10)
RTo 0.082-
mol. K
(E4-9.11)

FB
‘B = ‘TO 2FA0 - FA (E4-9.12)

TABLE E4-9.1. POLYMATH PROGRAM
Equations Initial Values

d(fa)/d(v)=ra 10
ka=2. I
kc=l. 2
ctOz.1
fa0=10
fb=2* (faO-fa)
ft=2*faO-fa
ca=ctO*fa/ft
cb=ctO’fb/ft
ra=-ka*(ca-cb**2/kC)
rb=-2 ’ra
vo = 0. v f = 100