Analytical Sciences


Abstract − Analytical Sciences, 19(7), 1075 (2003).

Mechanism of Gold Adsorption byPersimmon Tannin Gel
Akira NAKAJIMA,* Kaoru OHE,** Yoshinari BABA,** and TsuyoshiKIJIMA**
*Department of Chemistry, Faculty ofMedicine, Miyazaki Medical College, Kiyotake,Miyazaki 889-1692,Japan
**Department of Applied Chemistry, Faculty of Engineering,Miyazaki University, Gakuen-Kibanadai, Miyazaki 889-2192,Japan
Gold adsorption by persimmon tannin (PT) gelfrom a solution containing hydrogen tetrachloroaurate(III) was examined. Aflow-rate examination in a column system indicated the reduction of Au(III)ion to Au(0). XRD patterns clarified the existence of Au(0) on the gelwhich adsorbed gold. The gel could also adsorb colloidal Au(0) preparedindependently. A model consisting of ligand exchange, Au(III) reduction toAu(0), and resulting Au(0) adsorption by PT gel was presented for the goldadsorption mechanism.