The invention discloses a core-shell structure polymer magnetic nanosphere with a high Cr (VI) adsorption capacity and its preparation method and application. The preparation method includes: adding Fe.sub.3O.sub.4 powder into a mixed solution of water and ethanol, dispersing Fe.sub.3O.sub.4 powder in the solution evenly by ultrasound, sequentially adding resorcinol and formaldehyde into the suspension to adjust a pH, stirring and reacting to obtain Fe.sub.3O.sub.4@RF evenly dispersed in a chitosan solution, dropwise adding the prepared suspension into a mixed solution of paraffin and span 80, stirring for a period of time, adding a glutaraldehyde aqueous solution, stirring and reacting to obtain a magnetic chitosan nanosphere. The magnetic chitosan nanosphere prepared may be applied to adsorbing Cr (VI) in a water solution. Not only the magnetic chitosan nanospheres prepared has a high adsorption capacity for Cr (VI), but also can be quickly separated by an external magnetic field after adsorption.

The present disclosure provides methods and compositions for mitigating residue transfer from diatomaceous earth-based compositions. Some aspects of the disclosure provide a method of reducing residue transfer from a diatomaceous earth-based material by contacting a diatomaceous earth-based material with a content of a layered silicate solution sufficient to reduce residue transfer therefrom. Other aspects of the disclosure provide animal litter compositions including particles of a diatomaceous earth material at least partially coated by a layered silicate. Still other aspects of the disclosure provide a method of preparing an animal litter composition having reduced residue transfer, the method including forming an animal litter composition as a mixture of particles of a diatomaceous earth-based material and a layered silicate.

The invention relates to superabsorbent polymer that not only has excellent basic absorption performance, but also exhibits more improved permeability under pressure, and thus, can improve rewet property and leak inhibition property of hygienic products such as a diaper, and the like, and a method for preparing the same. The superabsorbent polymer comprises base resin powder comprising first crosslinked polymer of water soluble ethylenically unsaturated monomers having acid groups of which at least a part are neutralized; and a surface crosslink layer on the base resin powder, comprising second crosslinked polymer formed by additional crosslinking of the first crosslinked polymer by a surface crosslinking agent, wherein the surface crosslinking agent comprises a polymer type first surface crosslinking agent having number average molecular weight of 300 or more, and having plural hydroxy groups or epoxy groups.

Coated iron oxide (10) nanocrystal structures, superparamagnetic 10 nanoparticles, methods for synthesizing coated 10 nanocrystal structures, and methods for synthesizing superparamagnetic 10 nanoparticles are described herein. A coated 10 nanocrystal structure may comprise an iron oxide core, a manganese ferrite shell layer surrounding the core, and a bilayer coating surrounding the shell layer. The bilayer coating may include an inner oleic acid layer surrounding the shell layer and an outer layer surrounding the inner oleic acid layer.

The present invention relates to a process for the manufacture of microporous carbon materials to perform selective separations of nitrogen in gas mixtures such as hydrogen sulfide, carbon dioxide, methane and C.sub.2, C.sub.3 and C.sub.4.sup.+ hydrocarbons, with high efficiency, shaped of microspheres or cylinders from copolymers of poly (vinylidene chloride-co-methyl acrylate) with density of 1.3 to 1.85 g/cm.sup.3 or poly (vinylidene chloride-co-vinyl chloride) with density of 1.3 to 1.85 g/cm.sup.3, using two stages. The first stage consists of a surface passivation of the material by chemical attack in a highly alkaline alcohol solution, with the aim of effecting a precarbonization on the surface of the copolymer that during the pyrolysis process is not deformed and gradually develops microporosity. The material of the first stage presents, in the layer, percentages between 55% to 85% carbon, between 5% to 20% oxygen, and between 10% to 40% chlorine. The interior of the material presents lower percentages of carbon, between 30% to 65%, oxygen in the amount of between 2% to 6%, and chlorine in the amount of between 30% to 60%. The second stage consists of the gradual pyrolysis of the passivated copolymer, with the aim of developing microporosity and high surface area values; as well as during the melting and gas dehydrohalogenation stages thereof, the deformation of the material is avoided. The morphology of the copolymers are microspheres of 125 to 225 micrometers, or cylinders of 4 mm in height and 3 mm in diameter, which after pyrolysis reduce its size by 35% with respect to the initial one. The material of the second stage, which is already microporous carbon material, presents in the layer percentages between 90% to 100% carbon and between 10% to 0% oxygen.

The present invention provides: a porous fiber that exhibits both improved adsorption capacity, and suppressed exposure and detachment of particulates; an adsorption column filled with said porous fiber; and a blood purification system in which an adsorption column is connected to a water removal column. The porous fiber according to the present invention has a three-dimensional pore structure formed by a solid fiber, and satisfies all of the following conditions. (1) The porous fiber has particulates having a diameter of not more than 200 μm, and the percentage of area occupied by said particulates having a diameter of not more than 200 μm in a horizontal cross section of the three-dimensional pore structure is at least 3.0%. (2) The porous fiber does not contain said particulates having a diameter of not more than 200 μm in the region within 1.0 μm in the depth direction from the outermost surface.

The present disclosure relates to a method of synthesizing composites for removing heavy metals, including: preparing hollow hydroxyapatite particles including a functional group; preparing a composite in which magnetic oxide nanoparticles are combined on the hollow hydroxyapatite; and preparing a composite of hollow hydroxyapatite and metal particles by performing reduction annealing to the composite.

Provided is a production method for core-shell porous silica particles, the production method including: a preparation step of preparing an aqueous solution comprising non-porous silica particles, a cationic surfactant, a basic catalyst, an electrolyte, and an alcohol; a shell precursor formation step of adding a silica source to the aqueous solution to form a shell precursor on a surface of the non-porous silica particles; and a shell formation step of removing the cationic surfactant from the shell precursor to form a porous shell.

The present invention aims to provide core-shell particles that can be used in a method of separating a substance to be separated and that allow obtainment of a highly purified product. Each of a plurality of core-shell particles (C) of the present invention includes a core layer (P) as magnetic silica particles containing the magnetic metal oxide particles (A) and a shell layer (Q) that is a silica layer on a surface of the core layer (P), an average thickness of a plurality of shell layers (Q) being 3 to 3000 nm, wherein a weight percentage of the magnetic metal oxide particles (A) in the core layer (P) is 60 to 95 wt % based on a weight of the core layer (P), and the plurality of core-shell particles (C) have a particle size distribution with a coefficient of variation of 50% or less.

Composite particles contain a natural stone or aggregate core and a coating of two or more sorbent layers collectively containing at least two distinct kinds of sorbent materials effective for sorbing two distinct contaminants. One or both sorbent layers may be mixed with a water-absorbent, swellable clay that, upon contact with water, causes spalling or disintegration of the coating layer to release the sorptive material into a body of water such as a pond, ditch, stream, or riverbed. Additional swellable or protective layers may also be present. The composite particles are deployed into a pond, ditch, river, or streambed where the core of natural stone remains in the riverbed. The sorptive materials of the two different sorbent layers sorb and fix a wide range of contaminants, including both the heavy and light-weight hydrocarbons, from the water, and settle as a fine sediment. The sediment with sorbed contaminants is then removed by means such as hydraulic collectors or dredging.