Removal of Bromate from Water by Silver-Supported Activated Carbon

Batch experiments were conducted to make a comparison in bromate removal between the silver-supported activated carbon (silver-AC) and virgin grander activated carbon(GAC). The probable mechanism of the better behavior of silver-AC was discussed. The effect of initial bromate concentration, pH and co-exist anions were also investigated in the study. Results showed that the removal efficiency of bromate increased about 25% by using silver-AC, a much better removal. Bromate reduction by silver-AC increases as the solution pH decreases. And the bigger the initial concentration was, the larger of BrO₃ ^- removal capacity by silver-AC was. Cl^-, F^- and Br^- had a slight effect on the removal of BrO₃ ^- while SO₄ ^2-, CO₃ ^2-, NO₃ ^- and PO₄ ^3- showed a stronger influence. The affinity of the anions for silver-AC sites decreased in the following order CO₃ ^2- > PO₄ ^3- > SO₄ ^2- > NO₃ ^- > Br^- > Cl^- > F^- when the co-exist anion concentration was 10 mg/L.