Table 3.

Experimental design and responses.

No	Input variable			TC removal (%)
	Photocatalyst dose (g/L)	pH	TC initial concentration (mg/L)	Experimental	Modeling
1	2.1	7	30	70.50	68.61
2	2.1	7	30	70.40	68.61
3	4	7	55	65.98	66.17
4	2.1	7	30	70.00	68.61
5	0.2	10	30	6.71	6.92
6	0.2	7	55	24.60	24.75
7	4	7	5	92.00	92.18
8	4	10	30	37.68	37.68
9	0.2	2	30	9.63	9.54
10	2.1	10	5	36.26	37.00
11	4	2	30	31.84	31.84
12	2.1	7	30	67.33	68.61
13	2.1	7	30	67.00	68.61
14	0.2	7	5	33.27	31.4
15	2.1	10	55	28.98	28.24
16	2.1	2	55	58.98	56.53
17	2.1	7	55	59.34	62.36
18	0.2	10	55	1.92	1.71
19	2.1	7	5	72.00	71.12
20	2.1	2	30	60.38	62.79
21	0.2	2	5	10.89	10.98
22	0.2	7	5	29.68	31.4
23	4	7	30	81.43	81.05