عنوان مقاله [English]
Batch experiments were carried out to study chemical reduction of nitrate by metallic iron (Fe0) as a potential technology to remediate nitrate-contaminated water. The effects of different operating conditions such as initial pH of the solution, nitrate concentration, and Fe0 dosage on both nitrate reduction and removal efficiency were investigated. The results showed that the initial pH of the solution was very effective on nitrate removal which was over 95% within two hours at pH=2. However, nitrate removal decreased with increasing pH. Thus, only 18.2% of nitrate was removed at pH=5. It was also found that the ratio of iron to nitrate was important in nitrate removal, and a ratio of 400gFe0/gNO3- had the best efficiency for nitrate removal. The feasibility of using industrial wastes such as iron filings was also studied and it was found that the wastes could be desirable for nitrate removal.
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