Selenite Removal from Water

The present study aims at comparing the two most promising water treatment technologies for selenium removal. A techno‐economical comparison of Se(IV) uptake between the laboratory synthesized iron oxy hydroxide (FeOOH/2.5) with the highest positive surface density of 3.25 mmol [OH−]/g and adsorption capacity 4.3 μg Se(IV)/mg FeOOH/2.5 at pH 7, and coagulation/precipitation with the use of Fe(III) presenting an uptake capacity 3.2 μg Se(IV)/mg Fe was attempted based on the laboratory scale results. The evaluation showed that coagulation/precipitation treatment appears to be economically advantageous in comparison to adsorption process that was applied in Rapid Small Scale Column Tests (RSSCTs) with the FeOOH/2.5. It must be pointed out that for selection of the optimum removal method, other criteria should also be considered, such as post treatment requirements, water flow, labor cost, and maintenance requirements.