Performance Optimization of Chemical and Green Coagulants in Tannery Wastewater Treatment: A Response Surface Methodology Approach

Table 3

CCD matrix for coagulation experiments using cassava starch orange peel powder coagulants.

Run order	Independent variables		Responses
			Cassava starch			Orange peel powder
	Dosage (g/L)	pH,	COD removal, (%)	TSS removal, (%)	SVI, (mL/g)	COD removal, (%)	TSS removal, (%)	SVI, (mL/g)
1	10	4	24.89	68.48	35.12	14.49	53.37	51.47
2	7	6	30.19	64.15	16.90	19.71	61.99	32.89
3	10	8	27.77	61.22	11.36	15.83	58.10	58.53
4	7	6	33.02	64.85	17.27	24.35	59.61	32.35
5	7	6	31.94	61.88	16.34	20.87	57.24	33.59
6	7	3.17	28.03	74.42	25.36	17.97	57.67	25.57
7	4	4	36.11	68.21	16.97	15.94	68.68	19.60
8	11.24	6	31.07	65.66	27.74	15.65	56.16	66.89
9	2.76	6	38.93	65.15	21.13	2.90	61.12	30.17
10	7	6	31.25	64.65	16.63	22.32	60.91	33.13
11	7	8.83	30.56	61.45	14.05	18.55	50.08	42.48
12	7	6	30.19	61.02	17.76	20.29	60.69	32.30
13	4	8	38.19	59.79	23.68	5.22	42.07	38.05