Preparation and evaluation of potassium ferrate as an oxidant and coagulant for potable water treatment

Potassium ferrate was prepared using a new method, and its disinfection/coagulation performance for water treatment has been evaluated. The study results demonstrated that ferrate could act 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. The ferrate can effectively remove natural organic matter (as UV₂₅₄) and turbidity, and kills total coliforms (100%) at very low doses. In addition, under the optimal study conditions, the residual iron concentration and trihalomethane formation potential (THMFP) of the ferrate treated water are below that of drinking water standards.