Minimizing bromate formation with cerium dioxide during ozonation of bromide-containing water.
This work investigated the effect of several metal oxides including alpha-FeOOH, alpha-Fe(2)O(3), gamma-FeOOH, and CeO(2) on bromate formation potential (BFP) during ozonation of bromide-containing water. Results indicate that CeO(2) could most effectively minimize the BFP among these metal oxides taking ozonation alone as control. The BFP minimization by O(3)/CeO(2) favored a relatively low Br(-) concentration (i.e., <1.0mgL(-1)) and pH<7. Water temperature ranging from 5 to 25 degrees C had no significant impact on the percent reduction of BrO(3)(-). Further investigation indicates that the effective BFP minimization can be ascribed to neither the surface adsorption of BrO(3)(-) or Br(-) on CeO(2) nor the surface reduction of BrO(3)(-) to HOBr/OBr(-) by CeO(2). It seems to have relationship with the activity of surface Ce(IV) sites. The CeO(2) can lower the concentration of H(2)O(2) which is formed during ozone decomposition and promotes BrO(3)(-) formation. Another possible reason for the BFP minimization is that the CeO(2) could possibly reduce BrO() to HOBr/OBr(-) during the decomposition of H(2)O(2).
Zhang
Tao
T
School of Municipal & Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
Chen
Weipeng
W
Ma
Jun
J
Qiang
Zhimin
Z
D001959:Bromates / Q000737:chemistry*; D001966:Bromine / Q000737:chemistry*; D002563:Cerium / Q000737:chemistry*; D010126:Ozone / Q000737:chemistry*; D013997:Time Factors; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry; D014877:Water Pollution, Chemical / Q000517:prevention & control; D018508:Water Purification / Q000379:methods
D001959:Bromates; D014874:Water Pollutants, Chemical; D014867:Water; D002563:Cerium; C030583:ceric oxide; D010126:Ozone; D001966:Bromine