THEMODYNAMIC FEATURES OF ANION-EXCHANGE AND ANION-SELECTIVITY OF ALUMINUM/LITHIUM-LAYERED DOUBLE HYDROXIDE

Abstract

To understand the anion selectivity and thermodynamic features of the anion-exchange reaction of Al/Li-LDH, Cl^--Al/Li-LDH powder was synthesized with high crystallinity and purity. Anion-exchange experiments were then carried out at 300, 313, and 323 K. The order of anion selectivity was independent of temperature and was found to be the same as that of Mg/Al-LDH. Moreover, the anion-exchange reaction of Al/Li-LDH was controlled by the entropy term, which is expressed as the disorder of water and/or anions in the interlayer space of Al/Li-LDH.