Environmental Engineering Reference
In-Depth Information
TABLE 4.15
Relationships between
K
AP
and
T
for Some Organics in Ambient Air
log
K
AP
=
m
/
T
+
b
r
2
Compound
m
b
Reference
α
-HCH
−
2755
14.286
0.574
Bidleman and Foreman (1987)
Hexachlorobenzene
−
3328
16.117
0.687
Aroclor 1254
−
4686
19.428
0.885
Chlordane
−
4995
21.010
0.901
p
,
p
-DDE
−
5114
21.048
0.881
p
,
p
-DDT
−
5870
22.824
0.885
Fluoranthene
−
5180
20.80
0.682
Keller and Bidleman (1984)
Fluoranthene
−
4420
18.52
0.805
Yamasaki et al. (1982)
Pyrene
−
4510
18.48
0.695
Keller and Bidleman (1984)
Pyrene
−
4180
17.55
0.796
Yamasaki et al. (1982)
Fluoranthene
−
4393
21.41
Subramanyam et al. (1994)
Fluoranthene
a
−
6040
25.68
Subramanyam et al. (1994)
Phenanthrene
−
3423
19.02
Subramanyam et al. (1994)
a
Anannulardenudermethodwasusedtoreducesamplingartifactsresultingfromahigh-volumesampling
procedure. All other reported data in the table use the Hi-Vol sampling procedure. Bidleman and co-
workers obtained data from Columbia, SC,Yamasaki et al. from Tokyo, Japan, and Subramanyam et al.
from Baton Rouge, Louisiana.
where
P
s
(
l
)
is the subcooled liquid vapor pressure (atm),
N
s
is the number of moles of
adsorptionsitespercm
2
ofaerosol(mol/cm
2
)
,and
Δ
H
v
istheenthalpyofvaporization
83 cm
3
atm/mol K). In most cases
of the liquid (kcal/mol).
R
is the gas constant (
=
Δ
H
des
− Δ
H
v
, and hence the above equation simplifies to
10
4
P
s
(
l
)
N
s
A
p
1.6
×
K
AP
=
,
(4.105)
where
P
s
(
l
)
is expressed in mm Hg. If
K
AP
is expressed in
g/m
3
(a more conventional
unit) denoted by the symbol
K
AP
, we need to multiply by 0.001.
μ
E
XAMPLE
4.23 A
IR-TO
-P
ARTICULATE
P
ARTITIONING OF A
P
OLYAROMATIC
H
YDROCARBON
Calculatetheair-particulatepartitionconstantforapollutantinBatonRouge,Louisiana.
A typical value of specific area,
a
v
, for aerosols collected from Baton Rouge air was
estimated at 5
×
10
−
4
m
−
1
. The average particulate concentration,
C
sp
, in summer
time in Baton Rouge is 40
μ
g/m
3
. Therefore
A
p
=
a
v
/
C
sp
=
1.25
×
10
−
5
m
2
/
μ
g. For
physical adsorption of neutral compounds, Pankow (1987) observed that
N
s
is generally
continued
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