CHAPTER 21 • Solid Speciation and Selective Extraction Procedures
a
44.00
z
~
~ 43.70
.~
~
43.40
b
44.00
z
~
~ 43.70
Z
' =
~
43.40
13.20
13.20
13.50
13.80
14.10
longitude (0 E)
13.50
13.80
14.10
longitude (O E)
3.5
2.5
1.5
0.5
0.20
0.16
0.12
0.08
Fig. 21.6. Spatial distribution in Fraction 1 in the area of Ancona; a Cu (fig I-I); b Cd (fig tl)
Selective extraction. Modified SM&T protocol (accuracy tested on CRM).
463
Fraction 1. Exchangeable and acid soluble. Acetic acid 0.11 M (pH 2.8) was added to
the sediment, which was shaken overnight at room temperature. The extracts were
separated from the residues by centrifugation.
Fraction 2. Easily reducible phase. Hydroxylamine hydrochloride 0.1 M adjusted to pH 2
with nitric acid was added to the residue with the same procedure as the first extraction.
Fraction 3. Bound to organic matter and sulphides. The residue was put in a microwave Teflon vessel, and after the addition of 8.8 M hydrogen peroxide, left at room tem-
a
44.00
z
~
~ 43.70
.~
~
43.40
b
44.00
z
~
~ 43.70
Z
' =
~
43.40
13.20
13.20
13.50
13.80
14.10
longitude (0 E)
13.50
13.80
14.10
longitude (O E)
3.5
2.5
1.5
0.5
0.20
0.16
0.12
0.08
Fig. 21.6. Spatial distribution in Fraction 1 in the area of Ancona; a Cu (fig I-I); b Cd (fig tl)
Selective extraction. Modified SM&T protocol (accuracy tested on CRM).
463
Fraction 1. Exchangeable and acid soluble. Acetic acid 0.11 M (pH 2.8) was added to
the sediment, which was shaken overnight at room temperature. The extracts were
separated from the residues by centrifugation.
Fraction 2. Easily reducible phase. Hydroxylamine hydrochloride 0.1 M adjusted to pH 2
with nitric acid was added to the residue with the same procedure as the first extraction.
Fraction 3. Bound to organic matter and sulphides. The residue was put in a microwave Teflon vessel, and after the addition of 8.8 M hydrogen peroxide, left at room tem-