Results of ANOM Analysis for determination of the optimal conditions for (2D) ED^a.

Factor/level	j = 1	j = 2	j = 3	j = 4	M
pH/1	30.68	34.09	35.97	37.14	34.47
pH/2	32.71	36.52	34.24	35.88	34.84
pH/3	31.21	30.95	32.45	32.85	31.86
pH/4	21.16	25.96	34.33	33.46	28.73
Electrolysis time/1	30.68	32.71	31.21	21.16	28.94
Electrolysis time/2	34.09	36.52	30.95	25.96	31.88
Electrolysis time/3	35.96	34.24	32.45	34.33	34.24
Electrolysis time/4	37.14	35.87	32.85	33.46	34.83
2,4-D concentration/1	30.68	36.52	32.45	33.46	33.28
2,4-D concentration/2	34.09	32.71	32.85	34.33	33.49
2,4-D concentration/3	35.97	35.87	31.21	25.96	32.25
2,4-D concentration/4	37.14	34.24	30.95	21.16	30.87
Current density/1	30.68	34.24	32.85	25.96	30.93
Current density/2	34.09	35.88	32.45	21.16	30.89
Current density/3	35.97	32.71	30.95	33.46	33.27
Current density/4	37.14	36.52	31.217	31.26	34.03

^aThe boldface corresponds to the maximum value of the mean of the S/N ratios of a certain factor among the four levels.