Environmental Engineering Reference
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of 0.33 and is a structural parameter that is equal to 13 nm kJ/mol for this set of
materials. The micropore width, , is calculated as twice the micropore half-width,
. The Dubinin-Radushkevich-Stoeckli (DRS) equation was used to determine the
pore size distributions for several of the ACFs. Previously, Daley and co-workers
showed a good correlation between this theory and direct measurement of the
pore size distributions using STM.
The fitting of simulation data by the studied models was performed using the
genetic algorithm of simulation. All results were described (in the whole pressure
range) by a classical Dubinin-Astakhov adsorption isotherm equation, using the
values of the affinity coefficient tabulated in this review paper. Moreover, we ap-
plied the Dubinin-Izotova model and the Dubinin- Raduskevich-Stoeckli equa-
tion (also in the whole pressure range) in the form:
�
�
2
2
A
mx
N
x
-
pot
0
N
=
mDRS
×
exp
−
×
1+erf
€
0
‚
-
(79)
DRS
χ
1+2m
D
22
A
-
€
22
‚
-
D +D
21 2
mA
(1
+
erf (
0
))
1
+D
2
mA
22
ƒ
„
pot
pot
pot
D
2
where and are the values of adsorption and maximum adsorption, respectively,
is the adsorption potential, is a proportional coefficient ( is assumed as equal to
12 (kJ nm mol
−1
)), is the similarity coefficient, erf is the error function, and are
'dispersion' and mean of Gaussian distribution, respectively. The pore size distri-
bution was calculated using the correct normalization factor (i.e., from 0 up to):
2
χ
=
(80)
normDRS
x
�
�
Dπ+
€
2
(1
erf
0
)
‚
ƒ
„
D
2
Finally, the data were also described using the model proposed by Jaroniec and
Choma, where
( )
n
χ
x
= χ
normJCh
exp
−rζ
x
(81)
JCh
and
(
)
v
+
1
n
rζ
χ
=
(82)
normJCh
Ã(
v
+
1)
where is the Euler gamma function, is constant equal to and are the parameters
of Eqs. (80)-(82). The average micropore diameters from DI model were calcu-
lated using:
NH
+
N H
m
1
eff ,av1
m
2
eff ,av 2
H
=
(83)
eff ,av,DI
NN
+
m
1
m
2
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