Table 2.

Box-Benhen design and experiment data

Run	X1	X2	X3	Experimental data (mg/g)	Predicted data (mg/g)	Error (%)
1	−1	−1	0	2.02	1.98	1.98
2	−1	1	0	3.84	4.02	4.69
3	1	−1	0	4.87	4.59	5.75
4	1	1	0	5.23	5.46	4.40
5	0	−1	−1	2.45	2.57	4.89
6	0	−1	1	3.68	3.90	5.97
7	0	1	−1	4.47	4.22	5.60
8	0	1	1	5.53	5.28	4.52
9	−1	0	−1	2.57	2.54	1.17
10	1	0	−1	4.36	4.39	0.68
11	−1	0	1	3.57	3.54	0.84
12	1	0	1	5.79	5.82	0.52
13	0	0	0	5.71	5.62	1.57
14	0	0	0	5.64	5.62	0.35
15	0	0	0	5.50	5.62	2.18