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

Table 1

Effect of the irradiation time and hydrogen peroxide concentration in some physical-chemical parameters. Experimental conditions: 25°C and initial pH of 10.

Treatment	Time (min)	pH	Conductivity (S/cm)	H2O2 residual (%)
UV/0.3% H2O2	0	10.00 ± 0.02	811.00 ± 2.81	0.30 ± 0.01
	60	8.24 ± 0.12	947.00 ± 12.73	0.28 ± 0.04
	120	3.93 ± 0.09	982.50 ± 12.02	0.26 ± 0.03
	180	3.30 ± 0.08	1097.50 ± 8.25	0.23 ± 0.02
	240	3.95 ± 0.11	1345.00 ± 6.33	0.20 ± 0.03
UV/0.5% H2O2	0	10.00 ± 0.03	811.00 ± 2.82	0.50 ± 0.02
	60	8.89 ± 0.08	1068.00 ± 7.31	0.47 ± 0.03
	120	5.13 ± 0.13	1137.00 ± 10.15	0.44 ± 0.05
	180	4.00 ± 0.09	1241.00 ± 12.48	0.39 ± 0.03
	240	3.46 ± 0.12	1385.50 ± 8.42	0.30 ± 0.02
UV/0.7% H2O2	0	10.00 ± 0.03	811.00 ± 2.80	0.70 ± 0.01
	60	9.68 ± 0.13	1246.00 ± 5.81	0.67 ± 0.03
	120	6.75 ± 0.12	1293.00 ± 12.30	0.64 ± 0.02
	180	5.84 ± 0.10	1330.00 ± 7.05	0.58 ± 0.04
	240	5.55 ± 0.12	1445.00 ± 9.02	0.41 ± 0.02
UV/1% H2O2	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
UV/2% H2O2	0	10.00 ± 0.03	811.00 ± 2.80	2.00 ± 0.02
	60	9.77 ± 0.06	1890.00 ± 12.45	1.86 ± 0.04
	120	9.35 ± 0.14	1942.00 ± 6.39	1.63 ± 0.03
	180	8.40 ± 0.13	1957.50 ± 10.40	1.36 ± 0.03
	240	7.82 ± 0.10	2011.00 ± 8.27	1.04 ± 0.02
1% H2O2	0	10.00 ± 0.02	811.00 ± 2.79	1.00 ± 0.01
	60	9.81 ± 0.10	1488.00 ± 6.30	0.94 ± 0.02
	120	9.74 ± 0.09	1506.00 ± 5.49	0.90 ± 0.01
	180	9.69 ± 0.12	1510.00 ± 10.26	0.87 ± 0.02
	240	9.62 ± 0.08	1518.50 ± 11.10	0.86 ± 0.02
UV	0	10.00 ± 0.2	811.00 ± 2.80	—
	60	8.47 ± 0.11	832.00 ± 8.02	—
	120	7.86 ± 0.9	845.00 ± 12.91	—
	180	7.73 ± 0.8	859.00 ± 10.35	—
	240	7.55 ± 0.10	861.00 ± 7.48	—