A method for the sorption of phosphorous and/or nitrogen from a liquid, the method comprising the step of contacting the liquid with a composition comprising spongolite.

What is provided is a layered double hydroxide crystal for achieving higher ion-exchange capacity than that of the related art.

The layered double hydroxide crystal 1 according to the present embodiment is represented by Formula (1) and composed of a plurality of crystal grains 10 each of which has a lamination structure in which a plurality of plate-shaped crystals (11), (11), . . . are laminated, in which particle sizes of the plurality of crystal grains (10), (10), . . . are uniform on a microscale.

[Ni.sup.2+.sub.1-xFe.sup.3+.sub.x(OH).sub.2].[(Cl.sup.−).sub.X/2]  (1) (Where, 0.25<x≤0.9)

The disclosure provides a porous polymeric membrane having ionizable nitrogen functional groups at least at its surface, wherein such groups are associated with a hydroxide anion. The membranes are useful in the purification of polar solvents such as water and alcohols and are capable of removing trace amounts of anionic contaminants such as halides, phosphates, nitrates, nitrites, sulfites, and sulfates.

Proposed are a photocatalyst, including titanium dioxide particles including titanium dioxide (TiO.sub.2), a carbon material located on all or part of the surface of the titanium dioxide particles and including at least one selected from the group consisting of graphene, reduced graphene oxide (rGO), and carbon nanotubes (CNTs), and bimetallic nanoparticles supported on the carbon material and including first metal nanoparticles and second metal nanoparticles, and a water treatment method using the same. In the photocatalyst and the water treatment method using the same, the photocatalyst including bimetallic nanoparticles and graphene oxide is prepared, thereby exhibiting high reduction efficiency and high selectivity to nitrogen gas even without the use of an external electron donor.

A method for treating wastewater, comprising: (i) injecting a hydrate-forming gas (e.g., propane) into the wastewater under conditions of elevated pressure and reduced temperature to form a solid hydrate composed of the hydrate-forming gas and water from the wastewater; and (ii) separating the solid hydrate from the wastewater to result in removal of water from the wastewater, thereby resulting in partially dewatered wastewater, and optionally, (iii) lowering the pressure and/or raising the temperature of the solid hydrate to decompose the solid hydrate into reformed hydrate-forming gas and reformed water, and further optionally, recycling the reformed hydrate-forming gas for use in step (i) and/or capturing the reformed water from step (iii) and further decontaminating until suitable for release into waterway or for use in a process. The invention is also directed to an apparatus for practicing the method described above.

Compositions and methods for removing phosphates, nitrates and heavy metals from aqueous solutions.

A hybrid activated iron-biological treatment system and method for treating wastewater. The treatment system includes a combination of zero valent iron, ferrous iron, an iron oxide, and a denitrification microorganism.

Methods and systems for removing pollutants from water include one or more filter systems and a hybrid wetland system. Hybrid wetland systems may include a first pipe transporting water from a body of water to a settling tank, a first constructed wetland connected to the settling tank via a second pipe, and a first filter system removing pollutants from water passing through the second pipe. A second filter system is positioned within the first wetland to further remove pollutants. The system also includes a second constructed wetland connected to the first constructed wetland via a third pipe and a water control chamber. Filtered water exiting the first constructed wetland flows through the water control chamber, through the third pipe, and into the second constructed wetland. A fourth pipe extends between the second constructed wetland and the body of water, returning filtered water to the body of water.

Provided are a method of removing a perchlorate ion (ClO.sub.4.sup.−) and a nitrate ion (NO.sub.3.sup.−) which are toxic anions in wastewater using an anion-exchange resin on which a metal is supported, and more particularly an anion-exchange resin on which a hydrogen activating metal is supported or a hydrogen activating metal and a secondary metal are supported together and a method of removing toxic anions using the same. The toxic anions may be efficiently ion-exchanged and removed using an anion-exchange resin supporting a reduction catalyst, the regeneration of the anion-exchange resin may be facilitated, and the consumption of energy and the reducing agent may be reduced, thereby being usable in removal of toxic anions from an actual water purification system.

Methods for removing anions from an aqueous solution include contacting the aqueous solution with an initial organic phase composition in a primary stage to form a first mixture, the initial organic phase composition including a quaternary amine and a weak organic acid; separating a nitrate-depleted raffinate from the first mixture; mixing the remaining organic phase (now containing nitrate) with a first basic solution to obtain a second mixture; separating an aqueous phase sulfate-containing scrub solution from the second mixture; mixing the remaining organic phase with a second basic solution to form a third mixture; and separating the third mixture into an aqueous phase nitrate-rich solution and a secondary organic phase composition. The secondary organic phase composition can be recycled. The raffinate, the sulfate-containing scrub solution, and the nitrate-rich solution can then be further processed.