Bromate Inhibition of Bromide-Containing Water during Catalytic Ozonation with Fe-Mn-MCM-41

Employed bimetallic MCM-41 (Fe-Mn-MCM-41) synthesized by hydrothermal method to control bromate formation during ozonation of bromide-containing water. The influences including initial pH、t- butanol (TBA) and phosphate were investigated in this paper. The results showed that bromate formation increased with the increased pH in the range of 5.0-9.0, bromate inhibition efficiency for Fe-Mn-MCM-41 achieved 85.9% at pH 5 during catalytic ozoantion process. Bromate decreased in the presence of t- butanol (TBA) during both O3 and Fe-Mn-MCM-41/O3, suppression efficiency for bromate were 67.7% and 81.1% when adding 0.1 mM TBA. The addition of phosphate (1、5、10 mg/L) decreased bromate formation during ozonation and catalytic ozonation. Bromate decreased to 29.6% and 82.5% in O3 and Fe-Mn-MCM-41/O3 in the presence of 1 mg/L phosphate. Additionally, the concentration of HOBr and H2O2 were tested. Compared with ozonation process, the concentration of HOBr in catalytic ozonation was lower. The results showed that Fe-Mn-MCM-41 could prevent the production of HOBr to inhibit bromate formation. Besides, H2O2 is an inhibitor for bromate, more H2O2 was found in Fe-Mn-MCM-41/O3 rather than O3 process, it implied that Fe-Mn-MCM-41 enhanced the inhibition efficiency for bromate. Therefore, Fe-Mn-MCM-41was a catalyst which could decreased the bromate formation of bromide-containing water during catalytic ozonation process.