Removal of phosphorus and coliforms from secondary effluent using ferrate(VI)

The potassium ferrate(VI) was applied to treat secondary wastewater and its performance as both a disinfectant and a coagulant was investigated. In order to compare oxidation potential of the ferrate(VI) with that of chlorine, the different condition of doses and contact times were applied to the experiment for the same coliform. The disinfection rate of ferrate(IV) was faster than that of chlorine at the same concentration. The effect of ferrate(VI) supplementation on coagulation of phosphorus was examined and compared with other common coagulants. Ferrate(VI) reduced more than 80% of total phosphorous in the range of doses between 5. and 25 mg-Fe/L. The removal efficiencies of the ferrate(VI) appeared to be similar to those of alum but higher than other iron coagulants. The removal efficiencies of other contaminants in secondary effluent were not notable.