Copper-boron-ferrite (Cu—B—Fe) composites may be prepared and immobilized on graphite electrodes in a silica-based sol-gel, e.g., from rice husks. Different bimetallic loading ratios can produce fast in-situ electrogeneration of reactive oxygen species, H.sub.2O.sub.2 and .Math.OH, e.g., via droplet flow-assisted heterogeneous electro-Fenton reactor system. Loading ratios of, e.g., 10 to 30 wt. % Fe.sup.3+ and 5 to 15% wt. Cu.sup.2+, can improve the catalytic activities towards pharmaceutical beta blockers (atenolol and propranolol) degradation in water. Degradation efficiencies of at least 99.9% for both propranolol and atenolol in hospital wastewater were demonstrated. Radicals of .Math.OH in degradation indicate a surface mechanism at inventive cathodes with correlated contributions of iron and copper. Copper and iron can be embedded in porous graphite electrode surface and catalyze the conversion of H.sub.2O.sub.2 to .Math.OH to enhance the degradation. Inventive cathodes can be stable catalytically after 20 or more cycles under neutral and acidic conditions.

A dewatering apparatus for cellulosic materials includes a chamber for an aqueous solution of a cellulosic material, an inner electrode in the chamber, an outer electrode in the chamber about the inner electrode, and a power supply connected to the inner electrode and the outer electrode applying a voltage potential across the electrodes to remove water associated with the aqueous solution and to dewater the cellulosic materials.

A foam electrode comprising surface treatment by the steps of: 1) impregnating soft compressible polymeric foams with a conductive coating via sequential infiltration synthesis and 2) functionalizing the chemically altered voids with an ultrathin redox coating to enhance capacitive deionization (CDI). The redox coating will allow treated foam to absorb ions under the application of a bias, and mechanical compression/decompression. The CDI apparatus uses the void volume of the foam in the uncompressed state to flow liquids through it while the compressed state is used to enhance desalination by limiting the diffusion pathways for the ions to find an adsorption surface.

A water treatment system includes a water inlet that intakes water to be treated, a high voltage (HV) electrode having a porous metal surface area in a range of between 0.1 cm.sup.2 and 5 cm.sup.2 in fluid communication with the water, such that the water flows through the porous metal surface area of the HV electrode, a ground electrode disposed across a gap from the HV electrode, in fluid communication with the water, a high voltage power supply electrically connected to the HV electrode for generating spark plasma or pulsed electric fields having a rise time equal to or less than 60 nanoseconds (ns) and an amplitude greater than or equal to 30 kV/cm across the gap, thereby producing treated water, and a water outlet that discharges the treated water.

A carbon fiber filter includes a center filter body and carbon fiber yarn wound around the center filter body. The center filter body is hollow and includes a water outlet. A surface of the center filter body is provided with at least one inverted triangular groove. A plurality of through holes are arranged in the groove. The through holes and the water outlet are in communication with a hollow inner cavity of the center filter body. The carbon fiber yarn is wound in the groove with a constant force to form a filter layer.

Methods are described for treating aqueous solutions, including wastewater, to remove nitrogen-containing compounds using electrochemical processes. The method may be conducted electrolytically under an applied voltage or using endogenous current in a fuel cell arrangement. In some embodiments, energy is reclaimed in the form of hydrogen, methane, and other hydrocarbons or organic molecules. Microorganisms may be used as the catalyst for oxidation of the nitrogen-containing compound and/or reduction of hydrogen ions, carbon dioxide, or bicarbonate. Anaerobic or low-oxygen conditions may be used in the zone.

Methods are described for treating aqueous solutions, including wastewater, to remove nitrogen-containing compounds using electrochemical processes. The method may be conducted electrolytically under an applied voltage or using endogenous current in a fuel cell arrangement. In some embodiments, energy is reclaimed in the form of hydrogen, methane, and other hydrocarbons or organic molecules. Microorganisms may be used as the catalyst for oxidation of the nitrogen-containing compound and/or reduction of hydrogen ions, carbon dioxide, or bicarbonate. Anaerobic or low-oxygen conditions may be used in the zone.

A water prescribing system 1 is provided with a state storage unit 21 which stores a state variable relating to a physical constitution and health condition for each of a plurality of persons including a user, and a prescription unit 22 which creates a prescription of water suitable for the user based on the state variable.

A hydrogen-containing water generator includes a cathode portion of cylindrical shape that has a plurality of openings in a side thereof, an anode portion of cylindrical shape that is provided radially outside the cathode portion and has a plurality of openings in a side thereof, an electrolytic vessel that is transparent, has a cylindrical shape, and is internally provided with the cathode portion and the anode portion, a water supply part that supplies water into the cathode portion from one end side of the cathode portion; and a drain part that drains water inside the electrolytic vessel from the other end side of the cathode portion.

Processes for producing olefins may include electrolyzing an aqueous solution comprising metal chloride, where electrolyzing the aqueous solution causes at least a portion of the metal chloride to undergo chemical reaction to produce a treatment composition comprising hypochlorite. The processes may further include contacting at least a portion of the treatment composition with the sour water at a pH from 8 to 12, where the sour water comprises sulfides and the contacting causes reaction of the sulfides in the sour water with the hypochlorite to produce a treated aqueous mixture comprising at least metal sulfates and metal chlorides, where the metal sulfates are present in the treated aqueous mixture as precipitated solids. The processes may further include separating the precipitated solids from the treated aqueous mixture to produce a treated effluent comprising at least the metal chloride.