A method for producing microparticles and/or nanoparticles based on zero-valent metals directly inside a filtering media and/or for creating covering layers based on the zero-valent metals for covering. The filleting media includes the steps of introducing at least one solution containing metal salts in the filtering medium, introducing at least one solution containing inorganic reducing agents into the filtering medium. The steps of introducing the at least one solution containing metal salts and the at least one solution containing inorganic reducing agents inside the filtering medium is carried out in a way separated in time and/or in space to realize, in the filtering medium, a mixture of metal ions with the inorganic reducing agents as well as a chemical reduction of the zero-valent metals to form the microparticles and/or the nanoparticles and/or coverings based on the zero-valent metals inside of the filtering medium.

Methods and systems are provided for producing ionized alkaline solutions (e.g. ionized alkaline water) that exhibit long-term stability when stored at room temperature.

The present invention entails a method of treating an ion exchange regenerant stream containing selenate and removing the selenate from the regenerant stream through an oxidation-reduction process where selenate is reduced to selenite and the selenite is adsorbed onto an adsorbent which, in one embodiment, comprises iron oxide or iron oxyhydroxide. In particular, the method includes catalytically reducing the selenate to selenite in a selenate reduction reactor by reacting iron powder with the selenate in the presence of a nickel powder, which functions as a catalyst, to form selenite which is then adsorbed onto the iron oxide or iron oxyhydroxide.

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.

A system is provided for removing arsenic from water to safe levels at or below the EPA standards. The system is a hybrid spouted vessel/fixed bed filter system that significantly enhances/improves arsenic removal for drinking water using zero-valent iron (ZVI) particles. Movement of the circulating, iron-containing particles in a dense moving bed that forms on the spouted vessel bottom creates an abrasive “self-polishing” action among them that continuously generates colloidal iron corrosion products. This material then circulates with the water in the vessel and is removed and concentrated in a fixed bed filter. The colloidal material captured and immobilized in the filter has been shown to remove arsenic from contaminated water at very rapid rates.

An iron-boron alloy powder or an iron-boron alloy powder composition suitable for remediation of halogenated hydrocarbon polluted soil, water or groundwater as well as the use of the powder or powder composition. The boron-iron alloy powder suitable for remediation of polluted soil or waters may have 0.1-40% by weight of boron and inevitable impurities up to a content of 10% by weight. Further, a method for remediation of halogenated hydrocarbon polluted soil, water or groundwater.

In a method of manufacturing a bimetallic catalyst for reductively decomposing nitrate nitrogen, a powder including a trivalent iron oxide, a powder including a trivalent iron oxyhydroxide powder or a combination thereof is mixed in an aqueous solution. A copper precursor and a palladium precursor are mixed in the aqueous solution to form a precursor mixture. The precursor mixture is dried. The dried precursor mixture is fired at a temperature from about 300° C. to about 450° C. to form a fired product. The fired product is reduced by a reducing agent. A hydrochloric acid solution is mixed in the aqueous solution, or mixed with the copper precursor or the palladium precursor.

It discloses a method for preparing a magnesium-aluminum hydrotalcite-loaded nano zero-valent iron material for specifically removing perfluorooctanoic acid in a water environment and an optimized process for removing perfluorooctanoic acid thereby, and relates to the technical field of removing persistent organic pollutants in water using adsorption method and oxidation-reduction method and, in particular, to a composite material prepared by loading a nano zero-valent iron on magnesium-aluminum hydrotalcite using liquid phase reduction method.

A liquid concentrate composition for remediation of groundwater, said composition consisting of powdered iron in the amount of 30 to 70% zero-valent iron powder, such as 40 wt, 1 to 15 wt % of water, 0.1 to 1.5% of surfactant and 40 to 70 wt % of the organic carrier, wherein the organic carrier is added to the 100 wt % and optionally, organic electron donor solution and/or remediation chemical, wherein organic electron donor solution and/or remediation chemical is not exceeding 10 wt % of the liquid concentrate.

A method of removing or reducing the concentration of a contaminant in wastewater. The method involves combining wastewater and an elemental iron, comprising of zero valent iron, in a tank to produce treatment water. In this method the wastewater contains a contaminant consisting of: selenate [Se(VI)], selenite [Se(IV)], selenocyanate [SeCN.sup.−1], selenide [Se(−II)], and combinations thereof. The treatment water is then agitated with mechanical mixing and air sparging to produce a treated slurry. The treated slurry is then separated into a treated water stream and a contaminate stream.