Disclosed are a P—N heterojunction composite material supported on the surface of nickel foam, a preparation method therefor and the application thereof. The composite material is a supported catalyst which can be used to remove pollutants in water by means of photoelectrocatalysis. The method comprises firstly modifying, by means of a hydrothermal method, a layered nickel-iron bimetallic hydroxide nanosheet on the surface of clean nickel foam, and then modifying cobalt oxide nanowires on the surface of the layered nickel-iron bimetallic hydroxide nanosheet by means of a mixed solvent-thermal method, so as to obtain a P—N heterojunction catalyst composite material supported on the surface of nickel foam (Ni foam@NiFe-LDH/Co.sub.3O.sub.4). The composite material has a good response to visible light, which can greatly enhance the absorption and utilization of light, and is further beneficial to enhance the performance of the catalyst.

A wastewater treatment plant and related method comprise a treatment stage including a biological-process substage configured for growing unicellular organisms adapted to reduce contaminants in the wastewater which are dissolved, including at least one of organic matter and nitrogenous matter, by digestion thereof, and which are adapted to floc after digestion and a floc-removal substage downstream from the biological-process substage, relative to the flow of wastewater, and configured for substantially removing the unicellular organisms that have flocked. The treatment stage is configured to form majority and minority flows of treated wastewater, and the minority flow is configured to be recycled upstream of the biological-process treatment substage. The plant includes a heat transfer assembly configured for transferring heat from the majority flow of treated wastewater to the minority flow thereof to increase temperature of wastewater to be treated.

A two-stage treatment process for destroying per- and polyfluoroalkyl substances (PFAS) in an aqueous stream. The two-stage treatment process uses a combination of multifunctional crystalline molecular sieves, such as zeolites and zeotypes, to separate PFAS from the aqueous stream, catalytically decompose and defluorinate any PFAS molecules, and generate non-toxic waste products that are safe for disposal. The first stage includes adsorption of the PFAS within one of a pair of vessels containing porous, hydrophobic, hydrothermally stable molecular sieves, dehydration of the captured PFAS on the sieves, and catalytic ozonation of the captured PFAS molecules on the dried sieves. The second stage involves catalytic decomposition and neutralization of the ozonation results with one of a pair of vessels including a zeolite-supported CaO catalyst, catalytic oxidation of any toxic CO generated by the decomposition, and an acid wash for regeneration of the spent catalyst.

A sequential batch reactor wastewater treatment system and method, a material combination for practicing the method, and a fertilizer co-product deriving therefrom. A pH lowering agent comprising an acid lowers the pH of wastewater. A first compound including chitin or chitosan comprises a filtering medium, a coagulant, and a flocculant, and a second compound comprises an adsorbent and a pH raising agent. Wastewater is mixed and aerated subsequent to introduction of each of the first and second compounds, and flocculation yields treated water and a sludge byproduct that may be dewatered and further processed to yield a useful fertilizer co-product. Within the first compound, diatomaceous earth operates as a filtering medium and bentonite clay acts as a coagulant and filtering medium. Within the second compound, activated carbon, calcium oxide (CaO), and caustic soda (NaOH) are operative to adsorb, disinfect, and raise the pH of the wastewater.

A method and apparatus for removing an organosilicon component from a mixture are disclosed. The method and apparatus employ a copolymer of a di-alkenyl functional aromatic hydrocarbon and a polyorganosiloxane as the sorbent.

Systems for and methods of treating a fluid containing siloxanes, silanes and/or other silicon compounds. A hot box is configured to receive an initial flow of the fluid, react the flow with water at a temperature and pressure suitable for hydrolysis to generate a first treated flow, in which at least a portion is hydrolyzed to produce silicon dioxide and methane, and discharge the first treated flow. A solid removal mechanism can be configured to receive the first treated flow, separate at least a portion of the silicon dioxide as solid material, and discharge the remaining components as a second treated flow. Techniques of the present disclosure can lead to very low siloxane levels.

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 .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 .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 .OH to enhance the degradation. Inventive cathodes can be stable catalytically after 20 or more cycles under neutral and acidic conditions.

A method and system for water body algae control are provided. The method for water body algae control may include the steps of: withdrawing water from the water body; infusing a gas containing oxygen and/or ozone into the withdrawn water by generating nanobubbles of the gas within the water; and returning the infused water into the water body. The water body algae control system may include a nanobubble generator that may be configured to receive water that is withdrawn from a water body. An oxygen concentrator and an air compressor may be configured to provide a gas containing oxygen to the nanobubble generator and/or to an ozone generator, in which the nanobubble generator is configured to disperse nanobubbles of the gas containing oxygen and/or ozone into the water, and in which the nanobubble containing water is then directed back into the water body.

Monodisperse polystyrene microspheres are self-assembled on a conductive surface of FTO glass by vertical deposition method to prepare three-dimensional ordered photonic crystal opal template; the three-dimensional ordered photonic crystal opal template is immersed in a solution containing rhodium source, titanium source and strontium source, and is then calcined to prepare a rhodium doped strontium titanate inverse opal material; and the rhodium doped strontium titanate inverse opal material is added to water containing pollutants, and is then subjected to illumination and/or ultrasonic treatment to complete the removal of the pollutants in the water. The three-dimensional ordered macroporous rhodium doped strontium titanate inverse opal material may be applied in the field of photocatalysis. Under the action of external force, a built-in electric field formed by the spontaneous polarization of the material may effectively separate the photo-induced carriers, which may thus enhance the photocatalytic performance and improve the photocatalytic efficiency.

A water treatment apparatus including an underwater plasma discharge module is provided. The water treatment apparatus includes a dissolved air flotation device configured to remove foreign matter contained in water and an underwater plasma discharge module disposed at a preceding stage of the dissolved air flotation device and configured to cause a portion of the water to be introduced into the dissolved air flotation device to perform underwater plasma discharging, wherein the dissolved air flotation device comprises a mixing and coagulation basin configured to coagulate or flocculate the foreign matter contained in the water to form and grow flocs of the foreign matter, and a flotation basin configured to raise and remove the flocs by supplying microbubbles to the water passing through the mixing and coagulation basin.