Environmental Engineering Reference
In-Depth Information
TABLE 38.2
Speciation Analysis of Pure Al
13
Solutions under Aging:
Ferron Assay
Speciation
Conc.
(mol/L)
Aging
pH
Al
a
%
Al
b
%
Al
c
%
0.11
0
5.50
2.31
97.33
0.36
1
5.51
1.58
97.51
0.90
7
5.42
1.43
97.44
1.13
30
5.27
1.21
94.81
3.98
0.42
0
5.16
2.06
97.38
0.56
1
5.15
0.96
97.20
1.84
7
5.00
1.80
94.71
3.49
30
4.83
2.42
86.16
11.42
1.06
0
4.96
2.02
96.80
1.18
1
4.93
1.08
96.07
2.85
7
4.88
1.01
94.49
4.50
30
4.67
0.93
85.70
13.37
2.11
0
4.81
1.91
96.59
1.50
1
4.80
0.47
90.27
9.26
7
4.70
0.86
86.79
12.35
30
4.36
1.04
77.31
21.65
38.4 Particle Size Effect of Coagulation with Nano-IPF
With the puriied Al
13
available, a series of nano-IPFs can be tailor-made with different
PSDs; therefore, the PSD effect of coagulation with nano-IPF can be examined (Zhao et al.,
2013). Table 38.3 shows the speciation distribution of Al
13
aggregates by the ferron assay.
Figures 38.2 and 38.3 show the PSD effect of coagulation with nano-IPF at different doses
and pH conditions. From Figures 38.2 and 38.3, it could be seen that the coagulation with
nano-IPF exhibits a certain PSD effect in regard to the coagulant speciation and PSD fea-
tures therein. With increasing dose, the nano-IPFs exhibit eficient charge-neutralization
capability and turbidity removal as compared with traditional salts and low-Al
13
PAC l s .
This becomes more obvious in the aspects of loc formation kinetics and loc size (Figure
38.3).
TABLE 38.3
Speciation Distribution of Al
13
Aggregates by Ferron Assay
Al
T
Al
a
% Al
b
% Al
c
% Average PSD
a
(nm)
B
= 2.6 2.80 97.4 −0.20 8.9
B
= 2.7 2.80 94.3 2.90 11.9
B
= 2.8 2.40 92.8 4.80 23.1
a
Determined by photo correlation spectroscopy, the diameter of Al
13
is
around 2 nm;
B
= OH/Al ratio.
