Environmental Engineering Reference
In-Depth Information
(a)
O
APTS
BrCH
2
COBr
OH
(CH
2
)
3
-
NH
2
-
---
O-
O
(CH
2
)
3
NH
C
CH
2
Br
AT P
Aminopropyl-ATP
BrA-ATP
O
Acrylamide in water
Cu(I)Br, 1,10-phenanthroline
O
-
(CH
2
)
3
-
NH
--
C
CH
2
-
(CH
2
- CH)
n
-
C
NH
2
O
PAM-ATP
(b)
NH
2
O
NH
2
O
O
NH
2
H+
Hg(II)
+
-
O
HN
O
HN
Hg
X
NH
O
Hg
Monoamido-Hg structure
Diamido-Hg structure
figure 16.13
Preparation procedure of PAm-ATP (a) and the formation of the amido-Hg complexes (b).
table 16.1
adsorption capacities of atP nanofibrils
Adsorption capacities (mmol/g)
Hg(II)
samples
mB
mO
Bare ATP
0.033
0.028
0.023
PAm-ATP
1.12
0.073
0.024
system with an affinity order of Hg
2+
> Pb
2+
> Co
2+
[92]. It was found that the Hg
2+
adsorption capacity of the PAm/ATP pre-
pared under these conditions is more than sixfold compared with those of ATP and OATP. The adsorption process was rapid;
88% of adsorption occurred within 5 min and equilibrium was achieved at around 40 min. The equilibrium data fitted well with
the Langmuir sorption isotherms, and the maximum adsorption capacity of Hg
2+
onto PAm/ATP was found to be 192.5 mg/g.
The Hg
2+
ions adsorbed onto PAm/ATP could be effectively desorbed in hot acetic acid solution, and the adsorption capacity
of the regenerated adsorbents could still be maintained at 95% by the sixth cycle.
Hyperbranched aliphatic polyester (HAPe) had been grafted from the surfaces of the ATP via melt polycondensation of an
AB
2
-type monomer, 2,2-bis (hydroxymethyl) propionic acid (bis-mPA), with
p
-toluenesulfonic acid (
p
-TsA) as catalyst
