天然ゼオライトのリン酸イオン吸着

概要

論文の詳細を見る
Adsorption of phosphate ion of natural zeolites has been examined. Zeolite rocks used were naturally occurring clinoptilolite and mordenite. Cation exchanged zeolites used were prepared by the treatment with solutions of Al(NO_3)_3, AgNO_3, CaCl_2, and NiCl_2. Little or no adsorption was observed for the natural zeolites. It was found, however, that the treated zeolites adsorb phosphate ion. The adsorption amount versus pH curve shows different pattern between the kinds of exchanged cation. Adsorption tendency for different Ni-exchanged zeolites showed a similar feature being a flat region at pH range of 3-10, and a slow decreasing region above pH10. The Al-exchanged zeolite showed similar behavior to that of the Ni-exchanged zeolites. Adsorption amount of Ca-exchanged zeolites increased above pH10, e. g., 72meq/100g for the Ca-exchanged clinoptilolite at pH12.3. Characteristic adsorption curves were observed for the Ag-exchanged zeolites, which have a maximum at pH11.5-12. The amount of adsorption reached to about 63meq/100g. Adsorption of phosphate ion depends not only on the production of phosphate salts but also weak bonding with zeolite via cation.
日本粘土学会の論文
1994-09-27