Regeneration performance of spent granular activated carbon for tertiary treatment of dyeing wastewater by Fenton reagent and hydrogen peroxide

The efficacy of Fenton reagent and hydrogen peroxide for the regeneration of saturated granular activated carbon with biological effluent of dyeing wastewater was compared based on adsorption-oxidation recycle experiments. The catalytic performance of granular activated carbon and the necessity of ferrous ions were discussed. It was demonstrated that Fenton reagent or H2O2 was effective in destroying toxic organics and removing organic pollutants from the surface of granular activated carbon. The regeneration efficiency of granular activated carbon was about 50 % with Fenton reagent or H2O2 evaluated by chemical oxygen demand removals in adsorption. However, the synergic catalysis of granular activated carbon and ferrous ions enhanced the mineralization of organic pollutants and resulted in a higher regeneration efficiency of granular activated carbon evaluated by total organic carbon removals in adsorption compared with H2O2 alone.