Ferrate disinfects and coagulates drinking water and wastewater.
Ferrate both disinfects and coagulates drinking water or wastewater. Comparisons of (FeO42- ) treatment to conventional (chlorine + alum or ferric coagulants) have been made, and the results show: 1) for drinking water treatment, Ferrate can remove 10–20% more UV254 absorbance and DOC than ferric coagulants for the same dose, and the THMFP was reduced to less than 100 μg /L by Ferrate at a low dose, 2) Ferrate can easily achieve the disinfection targets e.g. >6 log10 inactivation of Escherichia coliform at a very low dose (6 mg/L) in comparison with chlorination, that required 10 mg/L plus the ferric coagulant at 4 mg/L. In wastewater treatment, Ferrate can reduce 30% more COD, and kill 3 log10 more bacteria compared to alum or ferric coagulants. Because of the small doses of Ferrate needed for treatment, less sludge is formed.
Jia-Qian Jiang, S. Wang, and A. Panagoulopoulos, (2006) Chemosphere Vol 63, Issue 2.
Also, it has been demonstrated that Ferrate acts as a dual-function chemical reagent (i.e., oxidant and coagulant) for drinking-water treatment, and performs better than ferric sulphate at lower doses for treating upland colored water. Ferrate can effectively remove natural organic matter and turbidity, and kills total coliforms (100%) at very low doses. In addition, under optimal study conditions, residual iron concentration and trihalomethane formation potential (THMFP) of Ferrate treated water fall below that of drinking water standards.
Jia-Qian Jiangg, B. Lloyd, and L Grigore, (2004) Env. Eng-g Science Vol 18, No. 5