Ln3+ Adsorption into an Yttrium-Hdehp Coordination Polymer through Exchange with Coordinated Yttrium Ion

摘要

An exchange between lanthanide ions (Ln~(3+)) in a solution and coordinated yttrium ions (Y~(3+)) takes place in a coordination polymer (CP) formed by Y~(3+) and di-(2-ethylhexyl) phosphoric acid (Hdehp). Through this cation exchange, Ln~(3+) is adsorbed on the CP depending on the coordination power with Hdehp. Accordingly, the Ln~(3+) with the larger atomic number is more preferably adsorbed into the CP. This adsorption is affected by the concentration of H~(+), C _(H+), in the solution. For example, at C _(H+)=10~(-5) M, Y~(3+) is replaced directly by the incoming Ln~(3+) with a 1:1 stoichiometry. In a limited higher C _(H+) region, the CP becomes a gel and the Ln~(3+)/Y~(3+) exchange is enhanced therein.