Abstract: A water purification apparatus and a water purification method capable of effectively using a layered double hydroxide and easily being applied are described. A water purification apparatus for removing a polluted substance from polluted water includes a solid-liquid separator that separates the polluted water and a solid material from each other, and a polluted substance remover that removes, by a layered double hydroxide, the polluted substance contained in the polluted water separated by the solid-liquid separator.

Abstract: Producing a filtration body formed of a layered double hydroxide having a crystallite size of 20 nm or less carried on a carrier including a thermally fusible fiber is described. The carrier is prepared that has a first mesh carrier having a first mesh size and a second mesh carrier provided above the first mesh carrier. The second mesh carrier has a second mesh size larger than the first mesh size. A layered double hydroxide in the form of granules is supplied toward the second mesh carrier. The first mesh carrier carries the layered double hydroxide that has passed through the second mesh carrier. The carrier is shaken so that a portion of the layered double hydroxide (e.g., at least one granule) passes through the first and second mesh carriers. Thereafter, the layered double hydroxide carried on the first mesh carrier is adhered by thermally fusing the thermally fusible fiber.

Abstract: A water purification apparatus and a water purification method capable of effectively using a layered double hydroxide and easily being applied are described. A water purification apparatus for removing a polluted substance from polluted water includes a solid-liquid separator that separates the polluted water and a solid material from each other, and a polluted substance remover that removes, by a layered double hydroxide, the polluted substance contained in the polluted water separated by the solid-liquid separator.

Abstract: A method for producing a layered double hydroxide compact can achieve production thereof at a lower cost for a short time by simplifying a process for producing a layered double hydroxide compact, and also can maintain a desired shape. The method for producing a layered double hydroxide compact is characterized by having a synthesis step of synthesizing a layered double hydroxide, a forming step of holding the layered double hydroxide after the synthesis step to a holding material, and a drying step of drying the layered double hydroxide held to the holding material until the water content thereof becomes equal to or lower than 30%.

Abstract: An object is to provide a filtration body capable of uniformizing the distribution of a layered double hydroxide in the filtration body and also preventing the surface of the layered double hydroxide from being covered with a binder or the like, thereby making it possible to improve the conventional filtration efficiency, and also a method for producing the same. The filtration body is formed of a layered double hydroxide having a crystallite size of 20 nm or less carried on a carrier including a thermally fusible fiber.

Abstract: There are provided an interlayer ion replacing method and an interlayer ion replacing apparatus which can efficiently replace the interlayer negative ions of hydrotalcite-like substances. The amount of positive ions which chemically-react with at least one of the interlayer negative ions or substituent negative ions is adjusted to facilitate desorption of the interlayer negative ions adsorbed by the hydrotalcite-like substances or to make the substituent negative ions easily adsorbed by the hydrotalcite-like substances, and the interlayer negative ions are replaced with the substituent negative ions.