Geoscience Reference
In-Depth Information
Fe ++ content of natural waters can reach 100 or 150 mg.I -1 (Stemmler et al.
2004), which is considerable. The solubility of Fe ++ is thus comparable
to that of the alkali and alkaline earth cations! But at pH 7, ferrous iron
is less soluble than silica.
+5
Fe
( OH
)
4
2
2
Fe
2
0
3
Fe
3
Fe
( OH
)
Fe
( OH
)
-5
Fe
( OH
)
2
Fe
( OH
)
2
4
Fe
( OH
)
2
Fe
( OH
)
-9
Fe
( OH
)
0
3
1
3
5
7
9
11
13
pH
Fig. 3.7
Solubility of ferric iron and ferrous iron.
The solubility of aluminium can be defined as shown in Figure 3.8
drawn by Fritz and Tardy (in Chamayou and Legros 1989).
Solubility of aluminium
3
Al
(
OH
)
3
H
Al
3
H
O
3
3
2
4
Al
(
OH
)
H
O
Al
(
OH
)
H
3
2
4
5
Stability zone of
gibbsite
6
Solubility zone of
Al OH
7
(
) -
Solubility
zone of
(
8
Al OH
)
2+
9
2
Al
(
OH
)
2
H
Al
(
OH
)
2
H
O
3
2
10
3
2
4
5
67 89 0 1 pH
Fig. 3.8 Solubility of aluminium. The curve has been slightly displaced to show
the straight lines better.
 
Search WWH ::




Custom Search