High energy radiation induced degradation of reactive yellow 145 dye: A mechanistic study

Gamma and UV radiation alone and in the presence of oxidant (H₂O₂) were employed for the degradation of reactive yellow 145 dye. The observed degradation was 82.73 and 77.93% under UV radiation, while 100 and 94.84% using gamma ray treatment for 50 and 100 mg/L drug initial concentrations along with H₂O₂, respectively. The reduction in COD was noted as 73 and 60% for 50 and 100 mg/L dye initial concentrations using gamma/H₂O₂ combined process, respectively. The pH was reduced significantly when the samples were treated with gamma/H₂O₂. The removal efficiency (G-value), dose constant (k), D_0.50, D_0.90 and D_0.99 of gamma-ray treated samples were also evaluated. The cytotoxicity and mutagenicity were measured, which reduced significantly in response of radiation treatment. The 44.45 and 55.56% decrease in cytotoxicity was shown by the Allium cepa, whereas 77.45 and 80.41% in case of hemolytic while 83.75 and 88.65% reduction in cytotoxicity was noted by the shrimp assay using UV/H₂O₂ and gamma/H₂O₂ treatments, respectively. The mutagenicity of dye solutions was reduced to 78.25 and 83.13% (in case of TA98), while 82.53 and 85.32% (in case of TA100) using UV/H₂O₂ and gamma/H₂O₂ processes, respectively. Results suggested that AOP can efficiently be used to degrade and detoxify the textile wastewater.