Environmental Engineering Reference
In-Depth Information
TABLE 4.17
Correlations of
K
VA
versus 1/
T
for Various Compounds
PAHs: ln
K
VA
=
(
A
/
T
)
+
B
Compound
A
B
Pyrene
10,227
−
35.95
Phenanthrene
9840
−
35.95
Anthracene
9773
−
35.95
Fluoranthene
10,209
−
35.95
Benz[
a
]anthracene
10,822
−
35.95
Benzo[
a
]pyrene
10,988
−
35.95
PCBs: log
K
VA
=
(
A
/
T
)
+
B
r
2
Compound
A
B
2,2
,5-PCB
3688
−
7.119
0.993
2,2
,5,5
-PCB
4524
−
9.307
0.992
2,2
,3,5
,6-PCB
4795
−
9.843
0.985
2,2
,4,4
,5,5
-PCB
6095
−
13.135
0.974
2,2
,3,3
,5,=5
,6,6
-PCB
5685
−
11.557
0.960
Source:
From Simonich, S.L. and Hites, R.A. 1994.
Environmental Science and Technology
28,
939-943; Komp, P. and McLachlan, M.S. 1997.
Environmental Science andTechnology
31, 886-890.
Note:
Note that
K
VA
has units of m
3
/mg of lipid and
K
VA
is dimensionless.
E
XAMPLE
4.24 E
STIMATION OF
U
PTAKE OF
A
TMOSPHERIC
P
OLLUTANTS
BY
V
EGETATION
Estimate the equilibrium concentration of pyrene on a sugar maple leaf with a lipid
content of 0.016 g/g. The air concentration is 10 ng/m
3
.
From Table 4.17, at 298 K, ln
K
VA
=
(
10, 227
/
298
)
−
35.95
=−
1.63. Hence
=
0.196 m
3
/mg lipid.
W
v
=
K
VA
φ
L
C
i
=
(
0.196
)
(16)
(
10
)
=
31 ng/g.
K
VA
4.7 ADSORPTION ON ACTIVATED CARBON FOR
WASTEWATER TREATMENT
Activated carbon has a high capacity to adsorb organic compounds from both gas
and liquid streams. It is perhaps the earliest known sorbent used primarily to remove
color and odor from wastewater. A large number of organic compounds have been
investigated in relation to their affinity toward activated carbon (Dobbs and Cohen,
1980). The data were correlated to a Freundlich isotherm and the constant
K
F
and
n
determined. Table 4.18 is for a selected number of organic compounds.
Activated carbon is available in both powdered and granular forms. The powdered
form can be sieved through a 100 mesh sieve. The granular form is designated 12/20,
20/40, or 8/30. 12/20 means it will pass through a standard mesh size 12 screen, but
Search WWH ::
Custom Search