Abstract: A novel anion adsorbent with extremely high anion adsorptive power, composed mainly of iron as a metal excellent in biosafety, is provided. The anion adsorbent contains, as an active ingredient, amorphous ferric hydroxide produced under such conditions that a ferrous species is present.

Abstract: The present invention provides agents for preventing, improving or treating phosphorus-related disorders and oral preparations; agents high in biosafety and phosphorus adsorptive power, which contain, as an active ingredient, ferric hydroxide as produced under such conditions that a ferrous species is present.

Abstract: A novel anion adsorbent with extremely high anion adsorptive power, composed mainly of iron as a metal excellent in biosafety, is provided. The anion adsorbent contains, as an active ingredient, amorphous ferric hydroxide produced under such conditions that a ferrous species is present.

Abstract: The present invention provides agents for preventing, improving or treating phosphorus-related disorders and oral preparations; agents high in biosafety and phosphorus adsorptive power, which contain, as an active ingredient, ferric hydroxide as produced under such conditions that a ferrous species is present.

Abstract: Organic media are derived from natural organic materials, which are coconut dust, simple coconut dust, or those containing coconut staple fibers, coconut pericarp chips, and are beaten bark, which is both broadleaf trees and needleleaf trees, and sawdust. These natural organic materials contain a lot of organic acids and salt (NaCl). The feature of the present invention is treatment using the modifying reagents to eliminate the organic acids and salt that adversely affect the cultivation of plants. The modifying reagents consist of at least one salt selected from among iron salts and aluminum salts, and the modified organic media obtained by modifying the natural organic materials with the modifying reagents. The natural organic materials are preferably coconut dusts, beaten bark, and sawdust. The modifying materials of 0.1 to 5 g is preferably applied to the natural organic materials of 100 g in dry weight.

Abstract: Organic media are derived from natural organic materials, which are coconut dust, simple coconut dust, or those containing coconut staple fibers, coconut pericarp chips, and are beaten bark, which is both broadleaf trees and needleleaf trees, and sawdust. These natural organic materials contain a lot of organic acids and salt (NaCl). The feature of the present invention is treatment using the modifying reagents to eliminate the organic acids and salt that adversely affect the cultivation of plants. The modifying reagents consist of at least one salt selected from among iron salts and aluminum salts, and the modified organic media obtained by modifying the natural organic materials with the modifying reagents. The natural organic materials are preferably coconut dusts, beaten bark, and sawdust. The modifying materials of 0.1 to 5 g is preferably applied to the natural organic materials of 100 g in dry weight.

Abstract: Water purifying substances produced by mixing raw material soil containing allophane expressed by:nSiO.sub.2.Al.sub.2 O.sub.3.mH.sub.2 Owhere, n is a number within the range of 1.3 to 2, and m is a number within the range of 2.5 to 3 at the maximum larger than 0, with water, and sintering a mixture thus obtained at 200.degree. C. to 700.degree. C., consequently to form porous sintered particles having a function of absorbing and fixing phosphoric acid. By scattering the water purifying substances around a lake, marsh or other body of water, phosphoric acid in sludge accumulated in the lake and so on can be effectively captured. The purifying effect of the water purifying substance can be improved by adding polyaluminum chloride and/or ferrous sulfate to the raw material soil.