Biochemical Reactions - A First Look
75
9C
! -0-3133?,
“ 9,
“ 9,
-0 -1 5 9 ,
“ 9,
-0.157
= f -0.68674
" 9 ,
— = 0.454 - i r ,f
“ 9j
aQ
- ^ = i-0 .3 1 3 3 7 „
- 9 ,
2 y
9
1 s s
(
2
)
Thus the black box model for this process becomes:
-C H 2O-0.\SY„NH2
+
Y]XCH
i
6
iO
052N0]5 + (j
0.3l33r„
-lY ^ C O ,
+
YsgCMin O +
(}-0.6867y„ -7 y w) 0 f !0 1)j +(0.4Sr„
- \Y n )H20 =
0
(
All stoichiometric coefficients are determined from the measured rates
qu q,
and
qt
- or from
q„ Y„,
and
Yv
It is easily seen that the carbon balance is satisfied:
-1 + ( j - 0.31337„ -
j Ysg) + ( i -
0.68677«
- i Y sg) + Ysx+Ysg =
0
(4)
The degree of reduction balance is automatically satisfied when HiO is taken to be one of the reaction
species - as is necessary when element balances are used:
- 4 + 4.127« + 4 |7 J?+ 6 - ( | - 0.68677«
7* ) = 0
(5)
In examples as simple as this it is of course not necessary to set the whole mathematical machinery into
action. The yield coefficient for NH3 is immediately given to be 0.15 and if a degree of reduction balance
plus a carbon balance is used one obtains
l = 7,x + 7,g + 7 „ + 7 ,c
4
= 4 .1 2 7 « + 4 * 7 * + 6 7 «
(6)
1 - r * -
-4 .1 2 7 « - 4 * 7 *
1
- r , - r v
'
q
-
0 . 3 1 3 3 4
- i r v >
4 - 4 . 1 2 f „ - 4 j l '„ ,
J - 0.6867 n . - l n , ;
which is the result obtained previously. If desired 7^ can be found from an H or an O balance.
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