A core-shell type amine-based carbon dioxide adsorbent is described, including a chelating agent resistant to oxygen and sulfur dioxide, to inhibit oxidative decomposition of amine. As a core, a porous support is employed on which an amine compound is immobilized, and, as a shell, an amine layer resistant to inactivity by sulfur dioxide is utilized. Such adsorbent exhibits high oxidation resistance because the chelating agent functions to remove a variety of transition metal impurities catalytically acting on amine oxidation. In addition, the sulfur dioxide-resistant amine layer of the shell selectively adsorbs sulfur dioxide to protect the amine compound of the core and, at the same time, the amine compound of the core selectively adsorbs only carbon dioxide. Sulfur dioxide adsorbed on the shell is readily desorbable therefrom at about 110 C. and thus remarkably improved regeneration stability is obtained during temperature-swing adsorption (TSA) processes in which sulfur dioxide is present.

A composite particle includes a solid particle, and a coating directly on the solid particle, the coating comprising a water-absorbing material. A layer includes a plurality of composite particles in contact, wherein the composite particles are comprised of: a solid particle; and a coating directly on the solid particle, the coating comprising a water-absorbing material. A method of fabricating composite particles includes combining solid particles with at least one precursor, cross-linker, and radical initiator in a solution to cause polymerization and formation of a water-absorbing coating on the solid particles resulting in composite particles, removing the solution and any unreacted precursors, and drying the composite particles. A method of forming composite particles includes mixing solid particles with at least one adhesive and with premade water-absorbing super absorbent polymer particles, curing the adhesive to form a monolithic block of solid particles with water-absorbing polymer coatings, and grinding the block to obtain composite particles.

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.

The core-shell type amine-based carbon dioxide adsorbent including a chelating agent resistant to oxygen and sulfur dioxide according to the present invention is an adsorbent which includes a chelating agent to inhibit oxidative decomposition of amine and has, as a core, a porous support on which an amine compound is immobilized and has, as a shell, an amine layer resistant to inactivity by sulfur dioxide, and a method of preparing the same. The amine-based carbon dioxide adsorbent including a chelating agent exhibits considerably high oxidation resistance because an added chelate compound functions to directly remove a variety of transition metal impurities catalytically acting on amine oxidation. In addition, the sulfur dioxide-resistant amine layer of the shell selectively adsorbs sulfur dioxide to protect the amine compound of the core and, at the same time, the amine compound of the core selectively adsorbs only carbon dioxide. In addition, sulfur dioxide adsorbed on the shell is readily desorbed therefrom at about 110 C. and thus remarkably improved regeneration stability is obtained during the temperature-swing adsorption (TSA) process containing sulfur dioxide.

This disclosure describes a process for preparing silica-coated calcium carbonate particles, involving the steps of preparing an aqueous carbonate slurry containing calcium carbonate particles, adding at least one silicate composition to the aqueous carbonate slurry to obtain a carbonate-silicate slurry, lowering a pH of the carbonate-silicate slurry by adding at least one acidic compound to obtain a pH-adjusted slurry containing the silica-coated calcium carbonate particles, and isolating the silica-coated calcium carbonate particlesin which at the adding of the acidic compound is controlled such that a final pH of the pH-adjusted slurry ranges from about 7 to about 10, and the silica-coated calcium carbonate particles include a porous coating having an average pore diameter ranging from 2 nm to 50 nm. This disclosure also describes articles and compositions containing the silica-coated calcium carbonate particles, as well as hollow silica spheres formed from the silica-coated calcium carbonate particles.

The super absorbent polymer according to the present invention has reduced 3-hour saline solution re-wet while having a high absorption rate and absorption against pulp, and thus can be used for hygienic materials such as diapers, thereby exhibiting excellent performance.

A production system for manufacturing composite porous solid articles is provided wherein the color of such articles is monitored to confirm that the articles, which are produced by heating and compressing mixtures of poly(vinylidene fluoride) binder powder (such as Kyblock resin from Arkema) and activated carbon powder, are fully cured. Adjustments to the processing conditions are made when a region of the article appears blue (indicative of incomplete curing).

A process for preparing hollow particles of aluminosilicates having a spherical shape of allophane type which are hybrid at the core, comprising: (a) having, at ambient temperature, an aqueous medium containing at least one aluminum precursor and one silicon alkoxide in an Al/Si molar ratio varying from 1 to 3, (b) carrying out, with stirring, the alkaline hydrolysis of said medium with gradual addition of at least one base in a base/Al molar ratio of 2.3 to 3, (c) maintaining, on conclusion of the addition of all of said base, stirring at ambient temperature until said medium is obtained in the clear state, and (d) heating the solution obtained at a temperature varying from 50 to 150 C. for 2 to 8 days, the combined stages (a) to (d) are carried out within a reactor consisting of a material which is chemically inert with respect to the reactants and expected aluminosilicate.

The invention provides superficially porous metal oxide particles with precisely controlled particle density and to methods for their preparation and use, as well as to separation devices (e.g., high pressure liquid chromatography) having superficially porous particles.

The present invention relates to superabsorbent polymer and a method for preparing the same. According to the method for preparing superabsorbent polymer of the present invention, superabsorbent polymer having improved rewet property and absorption speed can be provided.