An adsorbent for phosphoric acid-based anionic substances, that contains foamed glass, and that has a Ca2p concentration of 7.5 atom % or more or a Na1s concentration of 5.0 atom % or less at the surface thereof as measured by XPS analysis, and a half-width of Si2p peak of 2.4 eV or more. The adsorbent can also have a specific surface area of 45 m.sup.2/g or more or a pore volume of 2.5 cm.sup.3/g or more as measured by mercury intrusion.

An adsorbent for phosphoric acid-based anionic substances, that contains foamed glass, and that has a Ca2p concentration of 7.5 atom % or more or a Na1s concentration of 5.0 atom % or less at the surface thereof as measured by XPS analysis, and a half-width of Si2p peak of 2.4 eV or more. The adsorbent can also have a specific surface area of 45 m.sup.2/g or more or a pore volume of 2.5 cm.sup.3/g or more as measured by mercury intrusion.

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)

A bio-electrode composition includes (A) an ionic material and (B) a lithium titanate powder. The component (A) is a polymer compound containing a repeating unit-a having a structure selected from an ammonium salt, a sodium salt, a potassium salt, and a silver salt of any of fluorosulfonic acid, fluorosulfonimide, and N-carbonyl-fluorosulfonamide. Thus, the present invention provides a bio-electrode composition capable of forming a living body contact layer for a bio-electrode that is excellent in electric conductivity and biocompatibility, is light-weight, can be manufactured at low cost, and can control significant reduction in the electric conductivity even when the bio-electrode is wetted with water or dried; a bio-electrode including a living body contact layer formed of the bio-electrode composition; and a method for manufacturing the bio-electrode.

A bio-electrode composition includes (A) an ionic material and (B) a lithium titanate powder. The component (A) is a polymer compound containing a repeating unit-a having a structure selected from an ammonium salt, a sodium salt, a potassium salt, and a silver salt of any of fluorosulfonic acid, fluorosulfonimide, and N-carbonyl-fluorosulfonamide. Thus, the present invention provides a bio-electrode composition capable of forming a living body contact layer for a bio-electrode that is excellent in electric conductivity and biocompatibility, is light-weight, can be manufactured at low cost, and can control significant reduction in the electric conductivity even when the bio-electrode is wetted with water or dried; a bio-electrode including a living body contact layer formed of the bio-electrode composition; and a method for manufacturing the bio-electrode.

The amorphous inorganic anion exchanger of the present invention is represented by Formula (1) and has an average primary particle size observed with an electron microscope of at least 1 nm but no greater than 500 nm and an NO.sub.3 content of no greater than 1 wt % of the whole:
BiO(OH)  Formula (1).

The amorphous inorganic anion exchanger of the present invention is represented by Formula (1) and has an average primary particle size observed with an electron microscope of at least 1 nm but no greater than 500 nm and an NO.sub.3 content of no greater than 1 wt % of the whole:
BiO(OH)  Formula (1).

A composition, process and apparatuses for removal of one or more contaminant anions from water are provided. In an embodiment, the process includes treating the water with a composition comprising a layered metal hydroxy salt, wherein the layered metal hydroxy salt is a compound comprising (a) a metal (b) a framework hydroxide, and (c) a replaceable anion.

A composition, process and apparatuses for removal of one or more contaminant anions from water are provided. In an embodiment, the process includes treating the water with a composition comprising a layered metal hydroxy salt, wherein the layered metal hydroxy salt is a compound comprising (a) a metal (b) a framework hydroxide, and (c) a replaceable anion.

The present invention relates to a process for the preparation of Calcium Silicate Hydrate anion exchange membrane (cement paste) with an ionic conductivity of the order of 10.sup.−3 S/cm. The membrane can be formulated by mixing Ordinary Portland Cement (OPC) and water with the cement to water ratio of 1:0.45. After initial setting time, the membrane undergoes curing in 7% calcium chloride solution and the Cl.sup.− ions in the membrane is converted to OH.sup.− form by immersing into saturated Ca(OH).sub.2 solution with pH 14 and it has been washed to remove the excess alkali. This membrane has high mechanical strength (Ultimate Tensile Strength: 6.3 MPa) and does not deteriorate even at high temperature (up to 450° C.) and alkaline atmosphere (pH 11.5-14). Also disclosed is a method of producing in-situ formation of membrane electrode assembly. This invention encompasses a process for producing and using the membrane in water electrolysis and fuel cell.