Table 2 Range of the variables and the designed experiments as well as the corresponding responses for the PI process ([PQ] = 30 mgL−1, T = 25 °C)
Variables | Range and level | ||||
|---|---|---|---|---|---|
\(-\alpha\) | \(-1\) | \(0\) | \(+1\) | \(+\alpha\) | |
A: IO4− (mg L−1) | 110.45 | 30 | 60 | 90 | 9.54 |
B: pH | 2.29 | 4 | 6.5 | 9 | 10.70 |
C: TiO2 (mg L−1) | 15.91 | 50 | 100 | 150 | 184.09 |
Design matrix | |||||
|---|---|---|---|---|---|
Runs | Factors | DE (%) | |||
IO4− (mg L−1) | pH | (mg L−1) | (Exp.) | (Pred.) | |
1 | 90.00 | 9.00 | 50.00 | 76.61 | 74.62 |
2 | 60.00 | 6.50 | 100.00 | 69.90 | 70.07 |
3 | 110.45 | 6.50 | 100.00 | 86.56 | 87.71 |
4 | 30.00 | 9.00 | 150.00 | 45.70 | 52.70 |
5 | 60.00 | 6.50 | 184.90 | 77.42 | 80.32 |
6 | 60.00 | 2.29 | 100.00 | 25.53 | 35.98 |
7 | 60.00 | 6.50 | 100.00 | 70.43 | 70.07 |
8 | 60.00 | 10.70 | 100.00 | 69.62 | 62.64 |
9 | 90.00 | 4.00 | 50.00 | 68.82 | 62.64 |
10 | 60.00 | 6.50 | 15.91 | 56.18 | 59.81 |
11 | 30.00 | 4.00 | 150.00 | 47.58 | 40.72 |
12 | 30.00 | 4.00 | 50.00 | 36.56 | 28.52 |
13 | 9.54 | 6.50 | 100.00 | 25.54 | 30.33 |
14 | 60.00 | 6.50 | 100.00 | 69.89 | 70.07 |
15 | 90.00 | 4.00 | 150.00 | 82.79 | 74.84 |
16 | 60.00 | 6.50 | 100.00 | 69.62 | 70.07 |
17 | 60.00 | 6.50 | 100.00 | 69.35 | 70.07 |
18 | 60.00 | 6.50 | 100.00 | 70.43 | 70.07 |
19 | 30.00 | 9.00 | 50.00 | 44.09 | 40.50 |
20 | 90.00 | 9.00 | 150.00 | 84.14 | 86.82 |