A method of fabricating a magnetically-controlled graphene-based micro-/nano-motor includes: (a) mixing FeCl.sub.3 crystal powder with deionized water to obtain a FeCl.sub.3 solution; (b) completely immersing a carbon-based microsphere in the FeCl.sub.3 solution; transferring the carbon-based microsphere from the FeCl.sub.3 solution followed by heating to allow crystallization of FeCl.sub.3 on the surface of the carbon-based microsphere to obtain a FeCl.sub.3-carbon-based microsphere; (c) heating the FeCl.sub.3-carbon-based microsphere in a vacuum chamber until there is no moisture in the vacuum chamber; continuously removing gas in the vacuum chamber and introducing oxygen; and treating the FeCl.sub.3-carbon-based microsphere with a laser in an oxygen-enriched environment to obtain the magnetically controlled graphene-based micro-/nano-motor. A magnetically-controlled graphene-based micro-/nano-motor is further provided.

Disclosed are methods, apparatuses and systems for the remediation of contaminated soils, groundwater, water, and/or waste using a combination of reagents. The disclosed methods may be used to treat various recalcitrant halogenated substances, such as perfluoroalkyls and polyfluoroalkyls. Particular combinations of reagents that may be used in the disclosed methods include but are not limited to: (1) persulfate, oxygen and ozone; (2) persulfate, salt, oxygen and ozone; (3) persulfate, phosphate, and/or oxygen; (4) persulfate, phosphate, oxygen and ozone; (5) persulfate, phosphate, salt and oxygen (6) persulfate, phosphate, salt, oxygen and ozone; (7) oxygen and salt; and (8) air and salt. The disclosed methods may enhance destruction of organic contaminants in the liquid phase and may also control the rate of aerosol or foam formation relative to the rate of chemical oxidation and/or reduction/transfer.

A system and method of filtering waters contaminated by pollutants, in particular for removing heavy metals from said contaminated waters, said system comprising a duct for the transit of said contaminated waters, said system further comprising a tank of activated carbon powders in communication with said duct for the transit of said contaminated waters by introduction means adapted to introduce said activated carbon powders into said duct.

Polystyrene waste, such as Styrofoam® waste, and carbon nanofibers may be used to produce highly hydrophobic compositions or composites that can separate oil and water. Methods for purifying an aqueous solution may include: passing the aqueous solution, including a hydrophobic organic substance, over or through a surface including a polystyrene-CNF composition, thereby producing an aqueous product including less of the hydrophobic organic substance; and optionally, passing the aqueous product over or through the surface at least one more time.

Described herein is a PAH-degrading enzyme mixture obtained from a culture of PAH-utilizing microorganisms having been grown in presence of one or more enzyme inducers. Related methods and devices are also described.

A method and apparatus break down organic materials, typically contaminants, through oxidation. The method for the treatment of a volume of material, provides: a) introducing at least two electrodes into a location, the location containing the volume of material and the volume of material containing one or more species for treatment; b) providing connections between a voltage source and the at least two electrodes; c) applying a voltage of a first polarity to the connections for a first period of time, under the control of a voltage controller; d) applying a voltage of a second, reversed, polarity to the connections for a second period of time, under the control of the voltage controller; e) repeating steps c) and d) a plurality of times; preferably with steps c), d) and e) promoting oxidation of one or more of the one or more species for treatment.

A permeable reactive barrier having two or more layers of a geotextile fabric inoculated with a bioremediation microbe is provided. The permeable reactive barrier further includes two or more layers of coarse-grained geological material separating the two or more layers of geotextile fabric such that any pair of adjacent layers of geotextile fabric is separated by a layer of coarse-grained geological material. The permeable reactive barrier includes a perforated metal casing surrounding and containing the layers of coarse-grained geological materials and geotextile fabric.

A hierarchical catalyst composition comprising a continuous or particulate macroporous scaffold in which is incorporated mesoporous aggregates of magnetic nanoparticles, wherein an enzyme is embedded in mesopores of the mesoporous aggregates of magnetic nanoparticles. Methods for synthesizing the hierarchical catalyst composition are also described. Also described are processes that use the recoverable hierarchical catalyst composition for depolymerizing lignin, remediation of water contaminated with aromatic substances, polymerizing monomers by a free-radical mechanism, epoxidation of alkenes, halogenation of phenols, inhibiting growth and function of microorganisms in a solution, and carbon dioxide conversion to methanol. Further described are methods for increasing the space time yield and/or total turnover number of a liquid-phase chemical reaction that includes magnetic particles to facilitate the chemical reaction, the method comprising subjecting the chemical reaction to a plurality of magnetic fields of selected magnetic strength, relative position in the chemical reaction, and relative motion.

Disclosed are methods, apparatuses and systems for the remediation of contaminated soils, groundwater, water, and/or waste using a combination of reagents. The disclosed methods may be used to treat various recalcitrant halogenated substances, such as perfluoroalkyls and polyfluoroalkyls. Particular combinations of reagents that may be used in the disclosed methods include but are not limited to: (1) persulfate, oxygen and ozone; (2) persulfate, salt, oxygen and ozone; (3) persulfate, phosphate, and/or oxygen; (4) persulfate, phosphate, oxygen and ozone; (5) persulfate, phosphate, salt and oxygen (6) persulfate, phosphate, salt, oxygen and ozone; (7) oxygen and salt; and (8) air and salt. The disclosed methods may enhance destruction of organic contaminants in the liquid phase and may also control the rate of aerosol or foam formation relative to the rate of chemical oxidation and/or reduction/transfer.

A method for producing a nanocomposite sorbent comprising carbon nanotube-grafted acrylic acid/acrylamide copolymer which involves copolymerization of acrylic acid and acrylamide in the presence of an aqueous dispersion of carbon nanotubes. The method yields a nanocomposite sorbent material having a reversible adsorption capacity phenol of 5 to 2500 μg of phenol per mg of nanocomposite sorbent. Also disclosed is a method for removing organic pollutants from water using the nanocomposite sorbent.