Table 1 Box–Behnken design experimental runs
Runs | Factors | Responses | ||||
|---|---|---|---|---|---|---|
Methanol composition (%) | pH of aq. phase | Flow rate (ml/min) | Retention time | Theoretical plates | Tailing factor | |
1 | 60 | 3.5 | 0.8 | 7.56 | 2235 | 1 |
2 | 70 | 4 | 1.2 | 5.85 | 2466 | 1.35 |
3 | 70 | 3.5 | 1 | 5.32 | 2205 | 1 |
4 | 70 | 3.5 | 1 | 5.15 | 2257 | 1.04 |
5 | 70 | 3.5 | 1 | 5.15 | 2257 | 1.04 |
6 | 80 | 3 | 1 | 4.12 | 2136 | 0.85 |
7 | 80 | 4 | 1 | 4.13 | 2498 | 1.36 |
8 | 80 | 3.5 | 0.8 | 5.86 | 2245 | 1.03 |
9 | 60 | 3 | 1 | 7.45 | 2178 | 0.86 |
10 | 80 | 3.5 | 1.2 | 5.96 | 2305 | 1.05 |
11 | 70 | 3 | 0.8 | 5.12 | 2139 | 0.85 |
12 | 70 | 4 | 0.8 | 5.96 | 2496 | 1.41 |
13 | 60 | 4 | 1 | 7.55 | 2503 | 1.43 |
14 | 70 | 3.5 | 1 | 5.18 | 2265 | 1.05 |
15 | 70 | 3 | 1.2 | 6.23 | 2145 | 0.95 |
16 | 70 | 3.5 | 1 | 5.15 | 2245 | 1.05 |
17 | 60 | 3.5 | 1.2 | 6.98 | 2198 | 1.1 |