783
Complexation of Dissolved Organic Matter with Trace Metal Ions in Natural Waters
Table 1 Conditional stability constants (log
10 K)
of the M-DOM complexes in aqueous solution
Elements or groups
Conditional stability constants (log
10 K)
pH
References
Fulvic acid a
Humic acid a
Tryptophan or
protein or EPS a
Autochthonou
DOM or hydrophilic or hydrophobic a
Other organic
ligands a
Model ligands
Cu 2+
with COOH and OH
group
–
–
–
–
3.0–6.0
8.15
Martell and Smith
(1974)
Cu 2+
with NH
2 (NH
3 )
–
–
–
–
2.8
8.15
Martell and Smith
(1974)
Cu 2+
with ethanol amine
–
–
–
–
4.4
8.15
Martell and Smith
(1974)
Cu 2+
with glycine (NH
2 –CH
2 –
COOH or NH
3
+ –CH
2 –COO –
)
–
–
–
–
6.6
8.15
Martell and Smith
(1974)
Cu 2+
with ethylene diamine
(NH2–CH
2 –CH
2 –NH
2 )
–
–
–
–
8.5
8.15
Martell and Smith
(1974)
Cu 2+
with aspartic acid [HOOC–
CH(NH
2 )–CH
2 –COOH]
–
–
–
–
7.2
8.15
Martell and Smith
(1974)
Cu 2+
with iminodiaacetic acid
(HOOC–CH
2 –NH
2 –CH
2 –
COOH)
–
–
–
–
9.4
8.15
Martell and Smith
(1974)
Cu 2+
with diaminopropanol
–
–
–
–
8.3
8.15
Martell and Smith
(1974)
Cu 2+
with ethylenediamine-Nacetic acid
–
–
–
–
11.4
8.15
Martell and Smith
(1974)
Cu 2+
with diethylenetriamine –
–
–
–
13.0
8.15
Martell and Smith
(1974)
Cu 2+
with fulvic acid (modeled)
9.64 (K
1 ); 3.26 (K
2 ) –
–
–
–
?
Tipping (1994)
Cu 2+
with fulvic acid (modeled)
4.37 (K
2 )
–
–
–
–
6
Antunes et al. (2007)
Cu 2+
with fulvic acid (extraced
from soil)
5.30 (K
1 )
–
–
–
–
4
Cao et al. (2004)
(continued)