Environmental Engineering Reference
In-Depth Information
Figure 7.15: Schematic diagram of two leaching stages in catalyst pore network [From ref.
491
.
Reprinted with permission].
and
R
2
ρ
B
4
C
A
D
e
τ
D
=
(7.9)
By defining fractional (
χ
) conversion as:
r
2
R
2
Amount leached
Total foulants
χ
=
=
1
−
(7.10)
the mass balance equations can be reorganized to:
t
τ
D
=
χ
)
1
/
2
2(1
−
χ
)ln(1
−
+
χ
(7.11)
The chemical kinetics of the leaching process, assuming first-order reaction can be represented
schematically in the situation progressing from “B” to “C” and then to “D” as shown in
Fig. 7.15
. According to Levenspiel
[491]
, the chemical kinetics of the leaching process on a
cylindrical pore can be represented by:
t
τ
K
=
r
R
1
−
(7.12)
where
Rρ
B
kC
A
τ
K
=
(7.13)
and finally
t
τ
K
=
χ
)
1
/
2
1
−
(1
−
(7.14)
