Wastewater Treatment Using a Photoelectrochemical Oxidation Process for the Coffee Processing Industry Optimization of Chemical Oxygen Demand (COD) Removal Using Response Surface Methodology

Table 2

FCCD for COD removal by ECO/NaCl and ECO/CaCl₂ with UV/H₂O₂.

Run	Factor					COD removal efficiency (%)
	A (pH)	B (time) (min)	C (current) (amp)	D (electrolyte) (g/L)	E (H2O2) (ml)	NaCl (g) used	CaCl2 (g) used
1	5	30	0.3	1	2	91.246	91.904
2	9	30	0.5	2	4	95.783	96.442
3	9	30	0.3	1	4	93.708	94.367
4	5	30	0.5	2	4	92.408	93.067
5	9	50	0.3	2	4	95.025	95.683
6	7	40	0.4	1.5	3	96.683	97.342
7	5	30	0.3	2	2	91.471	92.129
8	9	30	0.5	2	2	93.593	94.251
9	7	60	0.4	1.5	3	98.158	98.817
10	7	40	0.4	1.5	3	97.067	97.725
11	7	40	0.6	1.5	3	98.467	99.125
12	5	30	0.5	2	2	92.575	93.233
13	5	30	0.5	1	4	92.708	93.367
14	7	20	0.4	1.5	3	97.179	97.838
15	5	50	0.3	2	4	91.571	92.229
16	7	40	0.4	1.5	5	98.640	99.298
17	9	30	0.3	2	4	95.438	96.096
18	5	50	0.3	1	4	93.179	93.838
19	7	20	0.5	1.5	3	97.204	97.863
20	9	30	0.3	1	2	94.455	95.113
21	5	50	0.5	1	2	92.575	93.233
22	5	50	0.3	1	2	91.579	92.238
23	5	50	0.3	2	2	91.129	91.788
24	9	50	0.3	1	4	94.458	95.117
25	7	40	0.2	1.5	3	95.063	95.721
26	5	30	0.3	2	4	93.071	93.729
27	5	30	0.5	1	2	92.025	92.683
28	9	30	0.3	2	2	95.354	96.013
29	9	50	0.5	2	2	94.413	95.071
30	7	40	0.4	1.5	3	98.558	99.217
31	7	40	0.4	0.5	3	96.954	97.613
32	9	50	0.5	2	4	95.654	96.313
33	9	30	0.5	1	2	95.079	95.738
34	5	50	0.5	2	2	94.250	94.908
35	9	50	0.3	1	2	95.294	95.952
36	5	30	0.3	1	4	90.294	90.952
37	7	40	0.4	1.5	3	98.379	99.038
38	7	40	0.4	1.5	1	95.096	95.754
39	9	30	0.5	1	4	92.779	93.438
40	7	60	0.4	1.5	3	98.300	99.992
41	9	50	0.5	1	4	95.279	95.938
42	9	50	0.3	2	2	95.813	96.471
43	7	40	0.4	2.5	3	98.796	99.454
44	5	50	0.5	1	4	92.846	93.504
45	7	40	0.4	1.5	3	98.217	98.875
46	9	50	0.5	1	2	93.454	94.113
47	5	50	0.5	2	4	94.213	94.871
48	7	40	0.4	1.5	5	97.771	99.913