Systems for treating wastewater containing organic nitrogen compounds are disclosed. The systems include a wet air oxidation unit having an oxidation zone, a catalytic zone, and a metal-based catalyst. Methods of treating wastewater containing organic nitrogen compounds are also disclosed. The methods include contacting the wastewater with an oxidant to produce a mixed liquor, contacting the mixed liquor with a metal-based catalyst to catalyze ammonia and produce a gas containing nitrogen and a liquid effluent containing nitrogen. Methods of retrofitting a wet air oxidation unit including providing a metal-based catalyst are also disclosed. Methods of facilitating treatment of wastewater in a wet air oxidation unit including providing a metal-based catalyst are also disclosed.

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.

The present invention discloses a lignin-based hierarchical porous carbon with high specific surface area and preparation method and application thereof. The present invention employs maleic anhydride, acrylic acid, and hypophosphorous acid to modify a lignin, then performs a cross-linking reaction with a glutaraldehyde-triethanolamine condensate to prepare a lignin graft-copolymerized by phosphino carboxylic acid copolymer, and then dropwise adding a soluble calcium salt solution and a soluble carbonate solution into the lignin graft-copolymerized by phosphino carboxylic acid copolymer dispersion successively, co-precipitates to prepare a lignin/nano CaCO.sub.3 complex, finally obtains a lignin-based hierarchical porous carbon with high specific surface area through carbonizing at a high temperature. The preparation method of the present invention may enable nano CaCO.sub.3 to be uniformly and stably dispersed in a three-dimensional network structure of the lignin graft-copolymerized by phosphino carboxylic acid copolymer, realizing full and uniform complexation of the lignin with nano CaCO.sub.3.

Provided are a treatment apparatus and a treatment method treating a waste cleaning liquid discharged from a process of producing an electrode of a lithium-ion secondary battery, in which a liquid component and a solid component are efficiently separated from each other, and the liquid component can be sufficiently collected and subjected to volume reduction treatment. The treatment apparatus includes: a stirring tank stirring the waste cleaning liquid; a liquid feed line that takes out the waste cleaning liquid from the stirring tank; and a thin film evaporator evaporating a cleaning liquid in the waste cleaning liquid to separate the solid component. Then, in the treatment method, the waste cleaning liquid is stirred in the stirring tank, the waste cleaning liquid is supplied to the thin film evaporator in a state in which the solid component is diffused, and the cleaning liquid in the waste cleaning liquid is evaporated.

The present invention aims to provide an activated carbon for adsorbing a molecular polar substance with excellent adsorption property to a molecular polar substance and regeneratability. The present invention provides an activated carbon for adsorbing a molecular polar substance obtained by an alkali activation method, wherein the activated carbon has an acidic functional group in an amount of 2.1 meq/g or more, a basic functional group in an amount of more than 0 to 0.6 meq/g, and a specific surface area of 1000 to 4000 m.sup.2/g.

The present invention relates to the technical field of wastewater treatment, and discloses a bioaugmentation treatment process for lithium battery producing wastewater. The method comprises the following steps: 1) introducing wastewater into a hydrolytic acidification tank, and adding Enterobacter sp. NJUST50 and activated sludge to the hydrolytic acidification tank for hydrolytic acidification treatment; 2) introducing the effluent into an anoxic tank, and adding Enterobacter sp. NJUST50 and anaerobic activated sludge for anoxic treatment; 3) introducing the effluent into an aerobic tank, and adding Enterobacter sp. NJUST50 and aerobic activated sludge for aerobic treatment; 4) introducing the effluent into an anoxic filter tank, and adding Enterobacter sp. NJUST50 and anaerobic activated sludge to the filter tank for treatment; and 5) introducing the effluent into a biological aerated filter tank, and adding a sludge mixture of Enterobacter sp. NJUST50 with aerobic activated sludge to the filter tank for treatment.

A process for preparing a granular composite adsorbent, that includes combining poly (diallyl dimethyl ammonium halide) and a clay mineral in water, maintaining the mixture under stirring, recovering a wet mass, forming the wet mass into granules and drying the granules to obtain the granular adsorbent having surface layer with positive zeta potential. The granular material and methods using the granular material in water treatment are also disclosed.

Use of Keplerate type polyoxomolybdates of the general structure Mo.sub.72M.sub.30, wherein M is selected from the group consisting of Fe, Cr, V or Mo.sub.2, for decontaminating aqueous media (water) from inorganic and organic pollutants.

The present invention relates to an aqueous composition comprising cells of at least one strain of a halophilic microorganism, and alkali sulfate in a concentration of at least 30 g/l based on the total volume of the aqueous composition. The present invention further relates to a method for treating a waste water, comprising obtaining or providing a waste water, contacting said waste water with cells of at least one strain of a halophilic microorganism, and thereby generating an aqueous composition comprising alkali sulfate in a concentration of at least 30 g/l, and incubating said aqueous composition under conditions which allow for the treatment of the waste water.

Disclosed is a method for degrading antibiotics by aqueous phase transfer catalysis using an anionic liquid and hydrogen peroxide, including: adding hydrogen peroxide to a wastewater containing the antibiotics to obtain a first mixture, and adjusting a pH of the first mixture to 3-4 to form an aqueous phase, and adding a catalyst to a water-insoluble ionic liquid to obtain a second mixture, and stirring the second mixture to form an ionic liquid phase, wherein the catalyst is selected from the group consisting of ferrocene, iron dodecyl sulfonate, ferrous dodecyl sulfonate, and copper dodecyl sulfonate; and mixing the aqueous phase and the ionic liquid phase in a volume ratio of (8-11):1 to obtain a mixed phase, and stirring the mixed phase to degrade the antibiotics.