| Abstract
| - The solid-state chelation of transition metal ions (Co2+, Ni2+, and Cu2+) from aqueous solutions into the lithium aluminum layered double hydroxide ([LiAl2(OH)6]Cl·0.5H2O) which has been pre-intercalated with EDTA (ethylenediaminetetraacetate) ligand has been investigated. The intercalated metal cations form [M(edta)]2- complexes between the LDH layers as indicated by elemental analysis, powder X-ray diffraction, and IR and UV−vis spectroscopies.
- The solid-state chelation of transition metal ions (Co2+, Ni2+, and Cu2+) from aqueous solutions into the lithiumaluminum layered double hydroxide ([LiAl2(OH)6]Cl·0.5H2O or LDH) which has been pre-intercalated with EDTA(ethylenediaminetetraacetate) ligand has been investigated. The intercalated metal cations form [M(edta)]2- complexesbetween the LDH layers as indicated by elemental analysis, powder X-ray diffraction, and IR and UV−visspectroscopies. If metal chloride or nitrate salts are used in the reaction with the LDH then co-intercalation of eitherthe Cl- or NO3- anions is observed. In the case of metal acetate salts the cations intercalate without theaccompanying anion. This can be explained by the different intercalation selectivity of the anions in relation to theLDH. In the latter case the introduction of the positive charge into LDH structure was compensated for by therelease from the solid of the equivalent quantity of lithium and hydrogen cations. Time-resolved in-situ X-ray diffractionmeasurements have revealed that the chelation/intercalation reactions proceed very quickly. The rate of the reactionfound for nickel acetate depends on concentration as ∼k[Ni(Ac)2]3.
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