Table 2 Experimental range and levels of the independent variables in terms of actual and coded factors in the optimization of enzyme amount and H2O2 flow rate
| Independent variable | Symbol | Level | ||
|---|---|---|---|---|
| −1 | 0 | 1 | ||
| Enzyme volume | X 1 | 25 | 50 | 75 |
| H2O2 concentration (%) | X 2 | 0.9 | 1.5 | 2.1 |
| H2O2 flow rate | X 3 | 0.3 | 0.4 | 0.5 |
| H2O2 volume | X 4 | 60 | 80 | 100 |