UV/H_2O_2/iron loaded rice husk ash based advanced oxidation process for the removal of safranin from wastewater

摘要

This study aims to investigate the removal efficiency of UV/H2O2/iron loaded rice husk ash (Fe-RHA) based advanced oxidation process for the removal of safranin in wastewater. The effects of several reaction parameters such as initial H2O2 concentration, initial pH and catalyst dose were studied. Moreover, Fenton-like process (Fe-RHA/H2O2), adsorption (Fe-RHA alone), UV alone and synergic process (UV/H2O2/Fe-RHA) were compared. Finally, the reuse performance of catalyst and removal of chemical oxygen demand (COD) was studied. The results show that synergic process (UV/H2O2/Fe-RHA) was found to be more efficient as compared with other processes. Furthermore, the decolorization of safranin was found to be the highest near acidic pH (pH = 3). The synergic process was also found to be effective near wastewater pH, achieving decolorization efficiency up to 46% at initial pH = 6. The results further reveal that significant amount (61% in 120 min) of COD was removed using UV/H2O2/Fe-RHA process. It is, therefore, concluded that the UV/H2O2/Fe-RHA synergic process is highly effective for the removal of dyes in wastewater.