title: Reduction-Induced Highly Selective Uptake of Cesium Ions by an Ionic Crystal Based on Silicododecamolybdate.
abstract: Cation adsorption and exchange has been an important topic in both basic and applied chemistry relevant to materials synthesis and chemical conversion, as well as purification and separation. Selective Cs(+) uptake from aqueous solutions is especially important because Cs(+) is expensive and is contained in radioactive wastes. However, the reported adsorbents incorporate Rb(+) as well as Cs(+) , and an adsorbent with high selectivity toward Cs(+) has not yet been reported. Highly selective uptake of Cs(+) by an ionic crystal (etpyH)2 [Cr3O(OOCH)6 (etpy)3]2 [α-SiMo12 O40 ]⋅3 H2O (etpy =4-ethylpyridine) is described. The compound incorporated up to 3.8 mol(Cs(+) ) mol(s)(-1) (where s=solid) by cation-exchange with etpyH(+) and reduction of silicododecamolybdate with ascorbic acid. The amount of Cs(+) uptake was comparable to that of Prussian blue, which is widely recognized as a good Cs(+) adsorbent. Moreover, other alkali-metal and alkaline-earth-metal cations were almost completely excluded (<0.2 mol mol(s)(-1)).
authors.affiliation: Department of Basic Science, School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan.
authors.forename: Saori
authors.initials: S
authors.lastname: Seino
authors.affiliation: Department of Basic Science, School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Kawahara
authors.affiliation: Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Ogasawara
authors.affiliation: Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
authors.forename: Noritaka
authors.initials: N
authors.lastname: Mizuno
authors.affiliation: Department of Basic Science, School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan. csayaka@mail.ecc.u-tokyo.ac.jp.|JST-PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan. csayaka@mail.ecc.u-tokyo.ac.jp.
authors.forename: Sayaka
authors.initials: S
authors.lastname: Uchida
keywords: cations; cesium; ion exchange; polyoxometalates; reduction