Abstract: Systems and methods for removing heavy metals such as selenium from wastewater with zero valent iron media. Air may be introduced directly into a reaction zone of a fluidized bed reactor filled with the media to catalyze treatment.

Abstract: Methods and systems for reducing the concentration of selenocyanate in water. In the methods and systems, water containing selenocyanate is treated an oxidant to provide oxidant-treated water, which is then contacted with a zero-valent iron treatment system comprising (a) a reactive solid comprising zero-valent iron and one or more iron oxide minerals in contact therewith and (b) ferrous iron.

Abstract: Methods and systems for reducing the concentration of selenocyanate in water. In the methods and systems, water containing selenocyanate is treated an oxidant to provide oxidant-treated water, which is then contacted with a zero-valent iron treatment system comprising (a) a reactive solid comprising zero-valent iron and one or more iron oxide minerals in contact therewith and (b) ferrous iron.

Abstract: A system containing a reactor vessel including zero valent iron media, a source of a conditioning additive, a source of a reaction additive, and a process control subsystem is disclosed. A method for reducing a concentration of one or more contaminants in contaminated water including contacting zero valent iron media with a conditioning additive, contacting contaminated water with conditioned zero valent iron media, and introducing a reaction additive is also disclosed. The conditioning additive and reaction additive may each contain an aluminum salt.

Abstract: Activated iron media and methods for generating and using the activated iron media. The method involves aqueous suspension comprising a zero-valent iron, ferrous iron, and an iron oxide to provide a settled solid and re-suspending the settled solid to provide an aqueous suspension containing an activated iron media.

Abstract: Methods and systems for reducing the concentration of selenium species in water, particularly water containing recalcitrant selenium species. In the methods and systems, water containing one or more selenium species is treated with permanganate to provide permanganate-treated water, which is then contacted with a zero-valent iron treatment system comprising (a) a reactive solid comprising zero-valent iron and one or more iron oxide minerals in contact therewith and (b) ferrous iron.

Abstract: Methods for reducing the concentration of one or more contaminants in water using zero-valent iron media. In the method, a mixed aluminum (III) and iron (II) salt solution is added to water containing one or more contaminants that is in contact with a zero-valent iron media that comprises (a) a reactive solid comprising zero-valent iron and one or more iron oxide minerals in contact therewith and (b) magnetite to provide an aqueous reaction medium. The aqueous reaction medium is contacted with the zero-valent iron media for a period of time sufficient to reduce the concentration of one or more of the contaminants.

Abstract: A powdered Iron-Selenide-Oxide sorbent composition, a method of using the sorbent, and a method for producing the sorbent is disclosed for removing mercury vapor from a gaseous stream. The exact ratios of Fe to Se are varied. The method for producing the sorbent comprises the steps of: preparing a base ferrous or ferric oxide (FeOx) media, conditioning the FeOx media with a slurry of ferrous selenite (FeSeO3)/ferrous selenate (FeSeO4), reducing the FeSeO3/FeSeO4 mixture by an elemental iron (Fe0) powder to incorporate selenide into the slurry, and dewatering and oxidizing the slurry. The sorbent can be used alone (or in combination with a powdered activated carbon material or an inert powdered material) by direct injection into the Hg-containing gas stream, by coating of a filter fabric used in bag house with the sorbent, or by using the sorbent in a packed bed gas stream filtration system.

Abstract: Systems and methods for removing heavy metals such as selenium from wastewater with zero valent iron media. Air may be introduced directly into a reaction zone of a fluidized bed reactor filled with the media to catalyze treatment.

Abstract: Methods for reducing the concentration of one or more contaminants in water using zero-valent iron media. In the method, a mixed aluminum (III) and iron (II) salt solution is added to water containing one or more contaminants that is in contact with a zero-valent iron media that comprises (a) a reactive solid comprising zero-valent iron and one or more iron oxide minerals in contact therewith and (b) magnetite to provide an aqueous reaction medium. The aqueous reaction medium is contacted with the zero-valent iron media for a period of time sufficient to reduce the concentration of one or more of the contaminants.

Abstract: A system containing a reactor vessel including zero valent iron media, a source of a conditioning additive, a source of a reaction additive, and a process control subsystem is disclosed. A method for reducing a concentration of one or more contaminants in contaminated water including contacting zero valent iron media with a conditioning additive, contacting contaminated water with conditioned zero valent iron media, and introducing a reaction additive is also disclosed. The conditioning additive and reaction additive may each contain an aluminum salt.

Abstract: A system containing a reactor vessel including zero valent iron media, a source of a conditioning additive, a source of a reaction additive, and a process control subsystem is disclosed. A method for reducing a concentration of one or more contaminants in contaminated water including contacting zero valent iron media with a conditioning additive, contacting contaminated water with conditioned zero valent iron media, and introducing a reaction additive is also disclosed. The conditioning additive and reaction additive may each contain an aluminum salt.

Abstract: Hybrid zero-valent iron systems and methods for treating a fluid containing a contaminant that removes or reduces the concentration of contaminants, such as toxic metals, metalloids, oxyanions, and dissolved silica.

Abstract: A powdered Iron-Selenide-Oxide sorbent composition, a method of using the sorbent, and a method for producing the sorbent is disclosed for removing mercury vapor from a gaseous stream. The exact ratios of Fe to Se are varied. The method for producing the sorbent comprises the steps of: preparing a base ferrous or ferric oxide (FeOx) media, conditioning the FeOx media with a slurry of ferrous selenite (FeSeO3)/ferrous selenate (FeSeO4), reducing the FeSeO3/FeSeO4 mixture by an elemental iron (Fe0) powder to incorporate selenide into the slurry, and dewatering and oxidizing the slurry. The sorbent can be used alone (or in combination with a powdered activated carbon material or an inert powdered material) by direct injection into the Hg-containing gas stream, by coating of a filter fabric used in bag house with the sorbent, or by using the sorbent in a packed bed gas stream filtration system.

Abstract: Methods and systems for reducing the concentration of selenium species in water, particularly water containing recalcitrant selenium species. In the methods and systems, water containing one or more selenium species is treated with permanganate to provide permanganate-treated water, which is then contacted with a zero-valent iron treatment system comprising (a) a reactive solid comprising zero-valent iron and one or more iron oxide minerals in contact therewith and (b) ferrous iron.

Abstract: Methods and systems for reducing the concentration of selenocyanate in water. In the methods and systems, water containing selenocyanate is treated an oxidant to provide oxidant-treated water, which is then contacted with a zero-valent iron treatment system comprising (a) a reactive solid comprising zero-valent iron and one or more iron oxide minerals in contact therewith and (b) ferrous iron.

Abstract: Activated iron media and methods for generating and using the activated iron media. The method involves aqueous suspension comprising a zero-valent iron, ferrous iron, and an iron oxide to provide a settled solid and re-suspending the settled solid to provide an aqueous suspension containing an activated iron media.

Abstract: A hybrid activated iron-biological treatment system and method for treating wastewater. The treatment system includes a combination of zero valent iron, ferrous iron, an iron oxide, and a denitrification microorganism.

Abstract: A system containing a reactor vessel including zero valent iron media, a source of a conditioning additive, a source of a reaction additive, and a process control subsystem is disclosed. A method for reducing a concentration of one or more contaminants in contaminated water including contacting zero valent iron media with a conditioning additive, contacting contaminated water with conditioned zero valent iron media, and introducing a reaction additive is also disclosed. The conditioning additive and reaction additive may each contain an aluminum salt.

Abstract: Hybrid zero-valent iron systems and methods for treating a fluid containing a contaminant that removes or reduces the concentration of contaminants, such as toxic metals, metalloids, oxyanions, and dissolved silica.