Optimized Removal of Hydroquinone and Resorcinol by Activated Carbon Based on Shea Residue (Vitellaria paradoxa): Thermodynamics, Adsorption Mechanism, Nonlinear Kinetics, and Isotherms
Table 5
Matrix of coded variables associated with experimental and predicted values of adsorption of hydroquinone or resorcinol on CAK-S.
Adsorption of hydroquinone (HQ) or resorcinol (R) on activated carbon CAK-S
No.
Coded levels
HQ
R
A
B
C
D
Exp qads
Prev qads
Residu
Qads exp
Qads prev
Residu
1
0
−1
0
0
24.12
27.17
−3.05
21.27
25.64
−4.37
2
−1
0
0
0
5.37
3.42
5.34
4.21
9.55
−5.34
3
+1
−1
+1
−1
45.11
44.28
0.83
33.58
29.49
4.09
4
−1
+1
+1
+1
2.37
1.56
0.81
2.13
0.21
1.92
5
0
0
0
0
23.82
22.52
1.30
16.44
16.60
−0.16
6
0
+1
0
0
24.82
22.81
2.01
20.90
16.50
4.40
7
0
0
0
0
23.91
22.52
1.39
17.14
16.60
0.54
8
0
0
0
+1
14.38
14.39
−0.01
5.65
5.17
0.48
9
−1
−1
+1
+1
3.03
3.09
−0.06
2.67
2.08
0.59
10
+1
+1
+1
−1
36.66
35.29
1.37
2.27
6.29
−4.02
11
−1
−1
−1
−1
15.17
13.88
1.29
12.74
12.38
0.36
12
+1
+1
−1
+1
13.00
14.06
−1.06
5.11
7.84
−2.73
13
0
0
0
−1
31.48
32.48
−1.00
12.31
12.76
−0.45
14
+1
0
0
0
18.85
21.76
−2.91
25.27
19.91
5.36
15
0
0
+1
0
23.75
24.21
−0.46
10.80
14.67
−3.87
16
−1
−1
−1
+1
3.04
3.54
−0.50
2.66
0.05
2.61
17
+1
+1
+1
+1
7.58
9.47
−1.89
4.51
3.45
1.06
18
+1
−1
−1
−1
42.62
42.56
0.06
26.53
29.86
−3.33
19
−1
+1
+1
−1
12.61
13.92
−1.31
4.33
3.54
0.79
20
−1
+1
−1
+1
2.41
3.84
−1.43
2.30
4.97
−2.67
21
0
0
0
0
22.08
22.52
−0.44
16.74
16.60
0.14
22
+1
−1
−1
+1
19.46
18.75
0.71
18.65
18.03
0.62
23
+1
+1
−1
−1
34.87
35.41
0.54
14.30
13.47
0.83
24
−1
+1
−1
−1
13.80
11.73
2.07
11.53
11.08
0.45
25
0
0
0
0
23.31
22.52
0.79
16.02
16.60
−0.58
26
−1
−1
+1
−1
15.17
13.88
1.29
12.97
11.65
1.32
27
+1
−1
+1
+1
19.46
18.33
1.13
18.57
20.43
−1.86
28
0
0
−1
0
23.93
24.49
−0.56
21.14
17.24
3.90
A: initial concentration (mg/L) of hydroquinone or resorcinol, B: pH of solution, C: contact time (min), and D: mass of activated carbon (mg).
