4.10 Outcome of Adsorption Investigation
89
Table 4.3
Kinetic variables for the binding of Cd(II) and Pb(II) ions onto GXCS at pH 5
Metal ion
First-order kinetic model
Second-order kinetic model
mg/L
K
1 (min)
q
e(Cal) (mg/g)
χ 2
R 2
q
e(Exp) (mg/g)
K
2 (g/mg min)
q
e(Cal) (mg/g)
R 2
χ 2
Cd(II)
40
0.03
13.5
0.01
0.99
15.54
3.23
× 10 −2
18.30
0.99
0.40
80
0.03
25.2
0.01
0.99
28.26
2.84
× 10 −2
31.10
0.99
0.26
120
0.04
39.8
0.04
0.98
42.76
1.75
× 10 −2
45.77
0.99
0.20
180
0.03
55.4
0.02
0.99
60.33
9.76
× 10 −4
64.56
0.99
0.28
220
0.03
94.5
0.15
0.83
98.45
6.98
× 10 −4
102
0.99
0.12
Pb(II)
40
0.03
11.3
0.35
0.96
83.22
3.8
× 10 −2
15.67
0.99
0.36
80
0.04
22.1
0.49
0.84
25.42
3.2
× 10 −2
28.45
1.00
0.32
120
0.04
36.3
0.15
0.92
38.70
3.3
× 10 −2
42.10
0.99
0.27
180
0.03
52.4
0.14
0.93
55.12
1.5
× 10 −2
60.64
0.99
0.50
220
0.04
87.6
0.09
0.94
90.45
9.0
× 10 −3
95.11
0.99
0.23