Experimental Design of Photo-Fenton Reactions for the Treatment of Car Wash Wastewater Effluents by Response Surface Methodological Analysis

Table 3

RSM for the three experimental variables in coded units and corresponding natural values.

Experiment number	Natural variable			Coded variable
	Fe^2+ (mg/L)	H2O2 (mg/L)	pH
1	30	350	6
2	30	450	6
3	50	350	6
4	50	450	6
5	40	350	3.5
6	40	350	8.5
7	40	450	3.5
8	40	450	8.5
9	30	400	3.5
10	50	400	3.5
11	30	400	8.5
12	50	400	8.5
13	40	400	6
14	40	400	6
15	40	400	6