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Bromate(BrO_3) is a disinfection by-product in drinking water, and its removal is very difficult especially at low levels.60 Co gamma rays were used to remove BrO_3in aqueous solution in this study. The effects of absorbed doses, BrO_3initial concentration, gas saturation, p H value and coexisting anions(Cl, NO 3, SO2 4and HCO 3=CO_3~(2 -))on BrO_3reduction were evaluated. After 4.0-k Gy irradiation of air-equilibrated solution of 30.7 lg/L BrO_3, the residual BrO_3was 8.3 lg/L, which is below the maximum contaminant level of drinking water. The BrO_3reduction rate increased with the dose, in the order of N2[ air [ O_2[ N_2O atmosphere under similar conditions. The results also show that high p H favored the BrO_3removal. According to the experimental results, it can be concluded that the efficiency of decomposing BrO_3by reactive species followed the order of e aq[ H [ HO_2 [ O_2. Coexisting Cl, HCO 3=CO_3~(2 -)and SO2 4ions have little effect on BrO_3removal, whereas NO_3can inhibit its removal as a result of competition with BrO_3for e aq.
Bromate (BrO_3) is a disinfection by-product in drinking water, and its removal is very difficult especially at low levels. 60 Co gamma rays were used to remove BrO_3 in aqueous solution in this study. The effects of absorbed doses, BrO_3initial concentration, gas saturation, p H value and coexisting anions (Cl, NO 3, SO 2 4 and HCO 3 = CO 3 2-) on BrO 3 reduction were evaluated. After 4.0-k Gy irradiation of air-equilibrated solution of 30.7 lg / L BrO 3, the The BrO_3 reduction rate increased with the dose, in the order of N2 [air [O_2 [N_2O atmosphere under similar conditions. The results also show that high p H favored the BrO_3removal. According to the experimental results, it can be concluded that the efficiency of decomposing BrO_3by reactive species followed the order of eaq [H [HO_2 [O_2. Coexisting Cl, HCO 3 = CO_3 ~ (2 -) and SO2 4ions have little effect on BrO_3removal, but NO_3can inhibit its removal as a result of competition with BrO_3for e aq.