This work investigated the degradation of humic acid (HA) in aqueous solution by electrochemical oxidation with Antimony- and Nickel-doped Tin oxide electrode (Ni-Sb-SnO2/Ti electrode) as the anode. Initial concentrations of HA ranged from 3 to 9 mg·L-1. Under such a concentration scope, the degradation of HA was a mass transfer controlled process. Degradation rate increased with the increase of HA initial concentration. Test on the effect of tert-butanol revealed that ·OH played an important role in the oxidation of HA. The absence of cation Ca2+ was beneficial to HA degradation, which suggested that both indirect and direct electrolyze happened during the whole electrochemical oxidation process. Alkaly (pH= 12) and neutral (pH= 7) conditions were benefical to HA degradation. |