Treatment of Sulfonated Azo Dye Reactive Red 198 by UV/H₂O₂

Table 2

Effect of the irradiation time and pH in some physical-chemical parameters. Experimental conditions: UV/1% H₂O₂ and 25°C.

Initial pH	Time (min)	pH	Conductivity (S/cm)	H2O2 residual (%)
3.0	0	3.00 ± 0.02	1067.00 ± 1.78	1.00 ± 0.01
	60	2.86 ± 0.05	1131.20 ± 6.32	0.95 ± 0.03
	120	2.73 ± 0.06	1357.40 ± 10.57	0.91 ± 0.02
	180	2.69 ± 0.07	1501.10 ± 11.34	0.87 ± 0.02
	240	2.85 ± 0.04	1394.34 ± 8.10	0.45 ± 0.01
6.0	0	6.00 ± 0.03	718.00 ± 2.02	1.00 ± 0.02
	60	3.54 ± 0.07	826.40 ± 9.12	0.95 ± 0.02
	120	2.90 ± 0.09	1119.80 ± 6.44	0.91 ± 0.04
	180	2.95 ± 0.10	1279.30 ± 10.71	0.80 ± 0.03
	240	3.14 ± 0.06	1195.60 ± 12.17	0.43 ± 0.02
8.0	0	8.00 ± 0.01	761.00 ± 2.31	1.00 ± 0.02
	60	3.64 ± 0.08	832.10 ± 5.54	0.94 ± 0.03
	120	3.25 ± 0.05	1192.50 ± 8.91	0.90 ± 0.02
	180	3.04 ± 0.06	1258.20 ± 13.77	0.80 ± 0.05
	240	3.57 ± 0.10	1250.70 ± 10.15	0.32 ± 0.03
10.0	0	10.00 ± 0.02	811.00 ± 2.81	1.00 ± 0.02
	60	9.96 ± 0.14	1591.00 ± 13.21	0.93 ± 0.05
	120	7.99 ± 0.10	1630.00 ± 8.36	0.88 ± 0.03
	180	6.66 ± 0.15	1563.50 ± 7.05	0.77 ± 0.03
	240	6.59 ± 0.09	1620.50 ± 6.87	0.31 ± 0.04