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Table 4 Summary of nonlinear regression results for Langmuir isotherm and Freundlich isotherm at 25 Cand35 C with unrefined and refined NBSK pulp. Isotherm Temperature ( C) Refining (rev) R 2 adj Q max (mg g - 1 ) K e (L mg - 1 ) Reduced chi-squared v 2 (mg 2 g - 2 )
Langmuir 25
0
0.46 2.34 ± 0.20
2.82 ± 1.73 0.13
35
0
0.95 6.31 ± 0.75
0.16 ± 0.06 0.16
25
3000
0.73 3.87 ± 1.28
3.75 ± 6.50 0.33
Isotherm Temperature ( C) Refining (rev)
Reduced chi-squared v 2 (mg 2 g - 2 )
K f (mg g - 1 (mg L - 1 ) - 1/n )
R 2
n
adj
Freundlich 25
0
0.38 12.82 ± 7.09 1.70 ± 0.25 0.15
35
0
0.94 2.71 ± 0.50 1.48 ± 0.31 0.19
25
3000
0.99 5.00 ± 0.04 2.57 ± 0.01 0.00
95% confidence limits after ±
7
3.5
(a)
25 o C unrefined
(b)
35 o C unrefined
6
3.0
5
2.5
4
2.0
3
1.5
2
1.0
Experimental Langmuir Freundlich
Experimental Langmuir Freundlich
1
0.5
0
0.0
0
10
20
30
40
50
0
20
40
60
80
100
C e (mg/L)
C e (mg/L)
5
(c)
25 o C refined
4
3
2
Experimental Langmuir Freundlich
1
0
-2 0
2
4
6
8 10 12 14
C e (mg/L)
Fig. 4 Nonlinear fit of Langmuir model and Freundlich model with experimental results at a 25 Cand b 35 C of LBG adsorption to unrefined NBSK pulp, and at c 25 C of LBG adsorption to refined NBSK pulp (3000 rev)
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