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In the previous works, we prepared adsorption gel from waste astringent persimmon by means of simple condensation reaction using concentrated sulfuric acid for crosslinking.It was found to be effective not only for selectively removing thorium(Ⅳ) and uranium(Ⅵ), radioactive elements, from trivalent lanthanides [1] but also for recovering gold from hydrochloric acid as fine particles of metallic gold [2].In the latter case, only gold was selectively adsorbed on the gel over other metal ions, not only base metal ions but also precious metal ions except for gold, which was considered to be attributable to the selective reduction of gold(Ⅲ) ion by polyphenol groups abundantly existing in the gel.