Application of Polytetrafluoroethylene (PTFE) Fiber Grafted Acrylic Acid as a
Cation Exchanger for the Removing of Cu2+,Pb2+and La2+
Zhi Peng WANG1,Jin ZHANG1, Zheng Pu ZHANG1*,Bao Gui ZHANG2,Yan Geng ZHANG3
1The
State Key Lab. of Adsorp.& Separ. of Funct. Polym. Materials, Nankai University, Tianjin China
2.Environmental Science College, Nankai University, Tianjin China
3The Tianjin Institute of Technological Physics, Tianjin China
2+
PTFE
D-152 resin
12
Cu
2+
Pb
3+
La
2.2
2.0
1.8
Effluent Concentration(mg/ml)
10
pH
8
6
4
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
2
0.0
-1
0
1
2
3
4
5
6
7
8
0
9
20
40
60
80
100 120 140 160 180 200 220 240 260
100
2+
Cu
2+
Pb
3+
La
80
60
40
20
0
0
Fig. 1 pH titration curve of both grafted
Fig. 2 The dynamic adsorption of Cu2+
,Pb2+ ,La3+by grafted PTFE fiber
The adsorption condition:[Cu ]0=1 mg/ml;
3+
[ Pb ]0=2 mg/ml; [ La ]0=2 mg/ml;
pH=5;SV(Speed Velocity)=7.5 BV/h
The desorption condition: SV=15BV/h
Cu
2+
15
Fig.3 The desorption of Cu2+ Pb2+ ,La3+ from
eluted ratio%=100%; Pb2+
eluted ratio%=98.1%;La3+ eluted ratio%=99.5%
References
1. B. W. Zhang, K. Fischer, D. Bienick, A. Kettrup, React. Polym., 1994, 24, 49.
2. L. Chen, G. L. Yang, J. Zhang, React & Funct. Polym., 1996, 29, 139.
3. D. Horak, M. J. Benes, G. Zaikov, et al., J.of Appl. Polym. Sci., 2001, 80, 913.
4. S. Lacour, J. C. Bollinger, B. Serpaud, et al., Analytica Chimica Acta, 2001, 428, 121.
* Email: Zhangzp@Nankai.edu.cn
10
the grafted PTFE fiber by different HCL elutions
2+
2+
5
HCL volume(ml)
V (ml)
NaOH volume(ml)
PTFE and D-152 resin
ion concentration of eluting solution(mg/ml)
There are many advantages for Ion exchange fibers produced from the natural fiber, i.e. the strong
hydrophilicity, the large surface area and the high speed of both adsorption and desorption for
organic compounds and metal ions. It has been used widely in biochemical separation, analysis, the
recovery of precious metals and the environmental protection1-4. But its application still was limited
because of the poor anticorrosion property.
There is excellent chemical stability for polytetrafluoroethylene (PTFE), it could be used in very
harsh conditions. Recently, a novel cation exchanger fiber was produced by irradiating grafting of
acrylic acid at the surface of the PTFE. The novel cation exchanger fiber not only has the advantages
of the commercial cation exchanger fiber, but also has a good corrosion resistance.
The pH titration curve of the grafted fiber was given in Figure 1. It could be found, there is a
sudden change when pH is from 6 to 10. This sudden change is different from the typical weakly
acid exchange resin (WAE).
This novel cation exchanger fiber was used for the removing of Cu2+, Pb2+ and La3+. The highest
adsorption capacity for Cu2+ Pb2+ and La3+, is 107.48 mg/g, 246.41mg/g, 150.30mg/g resp., when
pH is at 5 (Figure 2). It could be desorpted completely using 1 mol/ L HCl. ( Figure 3).
20