Assessment on the feasibility of bromate reduction by zero-valent iron (Fe0)
has been carried out in this study. The effects of iron types, iron surface
concentrations, mixing rates, pH, and concentrations of dissolved oxygen
(DO), natural organic matter (NOM), nitrate and nitrite were investigated with
batch tests. The observed rate constant (kobs) and the surface-area-normalized
rate constants (kSA) were obtained from pseudo-first-order
kinetics. The data revealed that irons from different manufacturers
demonstrated significant variations in bromate reduction. Monotonic increases
in the kobs were observed with increases in the iron surface concentration and
the mixing rate. The kobs were also found to increase with a decrease in pH,
especially when solution pH decreased from 6 to 5.5. The effects of DO,
NOM, nitrate and nitrite on bromate reduction were insignificant, presumably
due to the excessive Fe0 concentrations. Preferential reduction of bromate
might also contribute to the effective bromate removal when nitrate or nitrite
was present. Under the experimental conditions, soluble iron (Fe2+/Fe3+) at
concentrations of sub to a few mg/L (up to 6 mg/L) were observed only in the
beginning of all test runs. These findings indicate that chemical reduction by
Fe0 can be a very effective alternative when bromate removal is required. Includes 24 references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 320 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 10 |
| Published : | 06/15/2003 |
