Biomedical Engineering Reference
In-Depth Information
C,CO
2
CO
2
+
C,H
2
O
H
2
O +
C,N
2
N
2
+
C,P
P + …
Complete
combustion of
reactants
Complete
combustion of
products
+ O
2
+ O
2
H
c,R
H
c,P
Reaction of interest
H
R
(-
1
)A
1
+ (-
2
)A
2
+ …
P
A
P
+
P+1
A
P+1
+ …
FIGURE 3.5
Relationship between reaction of interests and the complete combustion state of the species involved.
and
X
D
H
c
;
P
¼
products
n
j
D
H
c
;j
(3.98)
j
¼
Substituting Eqns
(97) and (98)
into Eqn
(96)
, we obtain
n
j
X
X
X
N
S
DH
R
¼
DH
c
;j
products
n
j
DH
c
;j
¼
n
j
DH
c
;j
(3.99)
j
¼
reactants
j
¼
j
¼1
Similarly, we can compute the Gibbs free energy change for the interested reaction from the
combustion data:
X
N
S
DG
R
¼ DG
c
;
R
DG
c
;
P
¼
n
j
DG
c;j
(3.100)
j
¼1
Therefore, both heat of reaction and Gibbs free energy change can be computed from the
combustion data. The energy regularity relationships can be applied to compute the thermo-
dynamic properties when these data are not available. In bioprocess analysis, one often
defines the yield factor on the heat generation along the same line as the yield factor by:
D
H
R
n
j
YF
H
=j
¼
(3.101)
Table 3.3
shows the heats of combustion and approximate elemental compositions
(or Roel's formula) for some bacteria and yeasts.
3.10. CLASSIFICATION OF MULTIPLE REACTIONS
AND SELECTIVITY
A
B
B
A
C
D
C
Parallel
Series
Search WWH ::
Custom Search