Alkaline earth cation exchange with novel Na-3-mica: kinetics and thermodynamic selectivities
Alkaline earth cation exchange with novel Na-3-mica: kinetics and thermodynamic selectivities
复制标题
DOI：
10.1039/b314013j
复制
发表时间：
2004-03
影响因子：
--
通讯作者：
Ken-ichi Shimizu;K. Hasegawa;Yumiko Nakamuro;T. Kodama;S. Komarneni
中科院分区：
文献类型：
--
作者：
Ken-ichi Shimizu;K. Hasegawa;Yumiko Nakamuro;T. Kodama;S. Komarneni
The cation-exchange kinetics and thermodynamic equilibria for alkaline-earth metals by Na-3-mica [chemical composition of Na2.94(Mg5.55Ti0.07Fe0.04)oct(Al2.07Si5.83)tetO20F4·1.72H2O] with a high layer charge were investigated at room temperature. The Ba, Sr, Ca and Mg uptake kinetics were determined and first-order, modified Freundlich, parabolic diffusion and Elovich kinetic models were examined for the experimental data. The first-order model gave a relatively good fit throughout for these cations and indicated a kinetic selectivity order of Ca2+ Mg2+. The above basic studies on the selective cation exchange of the highly charged ion exchanger are of relevance in the separation, immobilization and disposal of 90Sr from aqueous nuclear wastes.
