Patent ID: 7767179

Claim:
A method for producing an adsorbent capable of selectively adsorbing an object compound, the method comprising: preparing a base material having a surface, in which at least part of the surface of the base material is formed of a material containing as its major component apatite which is represented by the composition formula Ca 10 (PO 4 ) 6 ((OH) 1-a X a ) 2 , where X represents at least one halogen element and 0≦a≦1; preparing a solution comprising ions of at least one metal element, wherein said metal element is at least one of a bivalent metal element, a trivalent metal element, a lanthanoid metal element, or an actinoid metal element; substituting at least part of the Ca of the apatite with the at least one metal element by bringing the base material into contact with the solution to obtain a substituted base material; and subjecting the substituted base material to heat treatment at 50 to 400° C. for 0.5 to 10 hours, wherein the heat treatment comprises a first heat treatment step carried out at a temperature of 50 to 250° C., and a second heat treatment step carried out at a temperature higher than that of the first heat treatment step, wherein the difference in a temperature between the first heat treatment step and the second heat treatment step is 50° C. or higher and wherein the base material and the substituted base material are not exposed to a temperature exceeding 500° C. for 4 hours or longer from the time of substituting at least a part of the Ca to the completion of production of the adsorbent.