Degradation of Acid Orange 7 at neutral pH by heterogeneous activation of peroxydisulfate using Co-GAC catalyst under UV irradiation

Granular activated carbon (GAC) supported cobalt catalyst (Co-GAC) was prepared and used as heterogeneous catalyst for the activation of peroxydisulfate (PS, ) under UV irradiation. The effects of some important reaction parameters such as PS concentration, catalyst addition, reaction temperature, and initial pH on the degradation of Acid Orange 7 (AO7) at neutral pH were investigated. Results showed that the decolorization efficiency by Co-GAC/PS process is enhanced in the presence of UV irradiation. The decolorization efficiency increased with the increase of PS concentration, catalyst addition, and reaction temperature, but decreased with the increase of initial pH. The decolorization efficiency was 96.2% and the chemical oxygen demand removal efficiency was 38.5% when initial pH value was 7, PS concentration was 1.0g/L and catalyst dosage was 0.8g/L.