[Problem] In an embodiment involving addition of a chelating agent in an upstream process of the process for production, such as the polymerization step, the residual ratio of the chelating agent in the final product, a particulate water-absorbing agent, is improved.

[Solution] A particulate water-absorbing agent having a poly(meth)acrylic acid (salt)-based water-absorbing resin as a main component, containing a chelating agent having a nitrogen atom and an inorganic reducing agent having a sulfur atom, wherein the particulate water-absorbing agent has a chelating agent ratio of 0.8 to 1.8, as calculated by the following procedures (a) to (c): (a) subjecting the particulate water-absorbing agent to a predetermined impact test; (b) sieving the particulate water-absorbing agent subjected to the impact test into a particle group 1 with a particle size of less than 300 μm and a particle group 2 with a particle size of 300 μm or more and less than 850 μm using a JIS standard sieve; and (c) quantifying a content C1 of the chelating agent present in the particle group 1 and a content C2 of the chelating agent present in the particle group 2, and then dividing the C1 by the C2.

A method for preparing a modified sodium fluoride adsorbent includes the following steps: S1. producing spherical particles of NiCl.sub.12.6H.sub.2O and porous NaF with a mass ratio of 1:3.0-3.5; S2. sintering the spherical particles in a vacuum environment at a temperature of 120-130° C. for 10-40 hours and at a temperature of 280-300° C. for 10-40 hours, respectively, to form an adsorbent intermediate with a NiCl.sub.2—NaF framework, wherein, a vacuum degree is less than or equal to 500 pa; and S3. treating the adsorbent intermediate by fluorine-nitrogen mixtures with high purity to obtain the novel sodium fluoride adsorbent having NiCl.sub.2—NaF framework. The modified sodium fluoride adsorbent can effectively separate chlorine trifluoride and hydrogen fluoride molecules, and the optimal adsorption rate of hydrogen fluoride is upgraded to more than 98%. While, the optimal adsorption rate of chlorine trifluoride is lowered down to around 3%.

A method of forming an activated carbon sorbent from a seagrass. The method involves treating a seagrass with a base solution to form an intermediate solid, drying the intermediate solid to form a precursor, and pyrolyzing the precursor at 600 to 1000° C. to form the activated carbon sorbent. Preferably the seagrass is Halodule uninervis. The activated carbon sorbent is used in a method of removing an organic pollutant from a contaminated water. Preferred organic pollutants removed are phenols, specifically 2,4-dimethylphenol and 2,4-dichlorophenol.

An object of the present invention is to provide a phosphorus adsorbent that is inexpensive and can exert high phosphorus adsorption performance. The present invention relates to a phosphorus adsorbent comprising incinerator ash, cement, and lanthanum.

An object of the present invention is to provide a phosphorus adsorbent that is inexpensive and can exert high phosphorus adsorption performance. The present invention relates to a phosphorus adsorbent comprising incinerator ash, cement, and lanthanum.

A SO.sub.2 adsorption material, a preparation method therefor and an application thereof, and a method for removing SO.sub.2 from flue gas containing SO.sub.2 are provided. The SO.sub.2 adsorption material contains a carbonized metal organic framework material and a sulfite loaded on the carbonized metal organic framework material, and the carbonized metal organic framework material is a carbonized material obtained by carbonizing a metal organic framework material. On the basis of the total weight of the SO.sub.2 adsorption material, the loading amount of sulfite is not higher than 10 wt %. The SO.sub.2 adsorption material has a relatively high SO.sub.2 adsorption capacity, and may be desorbed and regenerated by heating, and the adsorption capacity still remains at a relatively high level after multiple cycles of adsorption-desorption.

A composition comprising a compound of formula I:

##STR00001##

wherein n is 5, and R is methyl; and
the composition is in an essentially guest-free solid form.

This invention concerns ultra-high purity, ultra-high performance biogenic silica filtration products comprising diatomaceous earth. In particular, it relates to products comprising diatomaceous earth which is derived from ores that have been specifically selected for their naturally low centrifuged wet density and which have been intensively beneficiated to reduce extractable impurities to near or below detection limits. The low centrifuged wet density of the selected natural ore is either maintained or further reduced through the beneficiation process, which provides for filtration product/media with high particulate holding capacities able to provide for extended filtration cycle times.

A porous activated asphaltene material is described with a method of making and a method of using for the adsorption of a contaminant from a solution. The porous activated asphaltene material may be made by functionalizing solid asphaltene with nitric acid, and then treating the product with a metal hydroxide. The resulting porous activated asphaltene material exhibits a high porosity, and may be cleaned and reused for adsorbing contaminants.

The invention belongs to the field of eliminating pollutant gases. In particular, the invention belongs to the field of pollutant gas-absorbing material such as CO2, SO2, NOx and VOCs.

The present invention relates to a fresh composite or composite paste and a composite material comprising aggregates of recycled concrete, porous carbon, a binder and optionally water, as well as to the method for manufacturing the composite and the use thereof for sanitizing air (indoor or outdoor). The invention also relates to an article (for example, an anti-noise wall, a tunnel lining, an indoor decoration, an item of street furniture, etc.) comprising the composite according to the invention.