Ionic Strength Effects on Selenite Reduction Kinetics by Elemental Iron.

Zero valent iron has been used to treat a number of organic and inorganic contaminants, including selenium. Oxidized selenium forms, selenite and selenate, are removed from solution by reduction to elemental selenium and/or sorption to iron corrosion products. Using steel wool as an inexpensive source of elemental iron, we have shown that selenite reduction proceeds in two steps, a relatively long lag phase the length of which is strongly dependent on ionic strength, followed by rapid removal of selenium from solution.