Catalyst materials comprising iron and palladium are described. Also described are methods for preparing such materials. In addition, methods for remediating materials such as sediments and groundwater using the catalyst materials are described.

Devices and methods are provided for filtering contaminants or pollutants from water, such as rainwater or stormwater. The devices include a liquid filter comprising a tubular mesh enclosure containing a filling. The filling comprises compost particles and an activated carbon material. The compost particles have a bulk particle distribution of more than 30% less than 0.375 inches and at least 90% less than 2 inches. This unique combination of particle sizes and filling materials increases the removal efficiency of the filter. In addition, this filter media absorbs a broader range of industrial pollutants than conventional filters.

Reactive treatment cells (RTCs) are described in combination with sediment capping systems as a means for environmental remediation. RTCs include an impermeable housing defining an interior, a permeable ceiling and floor typically including filtration materials such as geotextiles, and at least one interior compartment for treatment reagents. One RTC includes a gabion-like cage structure retaining a geomembrane-supported geosynthetic clay liner (GM-GCL) housing, while a second embodiment includes a hard, cylindrical shell as a replaceable reagent cartridge. RTCs may be employed in initial capping system installations or retrofitted into existing capping systems. RTCs may include optional baffles, flow restrictors, floating discs, sensor probes, and two or more serial reagent zones or compartments.

A porous carbon material composite formed of a porous carbon material and a functional material and equipped with high functionality. The porous carbon material composite is formed of (A) a porous carbon material obtainable from a plant-derived material having a silicon (Si) content of 5 wt % or higher as a raw material; and (B) a functional material adhered on the porous carbon material, and has a specific surface area of 10 m.sup.2/g or greater as determined by the nitrogen BET method and a pore volume of 0.1 cm.sup.3/g or greater as determined by the BJH method and MP method.

A filter medium of the present invention includes a porous carbon material having a value of a specific surface area by a nitrogen BET method of 1×10.sup.2 m.sup.2/g or more, a volume of fine pores by a BJH method of 0.3 cm.sup.3/g or more, and a particle size of 75 μm or more, alternatively, a porous carbon material having a value of a specific surface area by a nitrogen BET method of 1×10.sup.2 m.sup.2/g or more, a total of volumes of fine pores having a diameter of from 1×10.sup.−9 m to 5×10.sup.−7 m, obtained by a non-localized density functional theory method, of 1.0 cm.sup.3/g or more, and a particle size of 75 μm or more.

An iron-carbon composite material and a preparation method thereof are disclosed. The iron-carbon composite material includes a three-layer core-shell structure, which successively includes a porous graphite carbon outer layer, an iron carbide intermediate layer and a nano zero-valent iron core from outside to inside. The present invention wraps nano zero-valent iron in porous graphite carbon and iron carbide, which can prevent the oxidation of nano zero-valent iron, while iron carbide effectively improves the ability to fix arsenic, realizing high efficiency and long-term use of nano zero-valent iron. Iron carbide may effectively adsorb and fix arsenic, and especially efficiently oxidize As(III) to relatively low-toxic As(V).

Measurement devices can be used for identifying concentration of arsenic species in water samples. The measurement devices can take the form of test strips including a substrate with at least one testing region that includes an amount of a testing medium. The silver reagent includes a polymer framework and a silver component that is stabilized by the framework, yet remains reactive enough to function as a colorimetric sensor for arsenic, e.g., ((Ag(H.sub.2btc))(Ag.sub.2(Hbtc))).sub.n. The initially substantially colorless testing medium exhibits a color change response when exposed to arsenic species, e.g., arsine, generated from samples including as little as 5 ppb arsenic, with an increasingly dark color as the concentration of arsenic is increased. Test strips fabricated with the silver coordination polymer display robust stability towards both light and water, allowing for an alternative to mercury-based field test kits in real-world field tests under direct sunlight and high humidity conditions.

A composition for remediation of soil and groundwater containing halogenated compounds. The remediation composition includes an elemental iron-based composition, which may include activated carbon capable of absorbing the halogenated compounds with numerous pores impregnated with elemental iron. The remediation composition further includes a first bioremediation material including a blend of one-to-many organisms capable of degrading the halogenated compounds. The remediation composition includes an organic compound or polymeric substance and a second bioremediation material including a blend of one-to-many organisms capable of degrading the organic compound or polymeric substance over time (e.g., 20 to 365 or more days to provide a time release substrate-creating material or platform) into smaller molecules or compounds used by the organisms in the first bioremediation material while degrading the halogenated compounds. The organic compound may be a complex carbohydrate such as food grade starch, chitin, or other complex carbohydrate such as one with low water solubility.

A contaminant-sequestering coating includes a network of hydrolyzed silane compounds. The hydrolyzed silane compounds include a hydrophilic polar head region, a hydrophobic linker, and an anchor region including a silicon atom. The network of hydrolyzed silane compounds is devoid or substantially devoid of fluorine atoms. Methods of destroying one or more perfluoroalkyl and/or polyfluoroalkyl (PFAS) compounds present in a contaminant-containing liquid are also provided.

An adsorbent for a target compound can include porous carbon particles having pores with a predominant pore size less than 10 nm, and magnetic nanoparticles (MNP) nucleated on the carbon surface and within the pores of carbon particles to provide a carbon magnetic nanoparticle adsorbent (C-MNA). A method for removing target compounds with an adsorbent, a system for removing contaminants from a liquid, and a method for adsorbing target compounds from a fluid are also disclosed.