Abstract
The intercalation behavior of various saturated aliphatic mono- and dicarboxylate ions ([chemical formula], [chemical formula]) into Mg-Al and Zn-Al layered double hydroxides (LDHs) by the reconstruction method using each oxide solid solution precursors was investigated at 25℃. The oxide precursors prepared by the thermal decomposition of synthetic LDHs were found to intercalate easily these carboxylate ions with reconstructing the LDH layer structure. The interlayer distance and degree of crystallinity of the LDH products diversely varied with the intercalated amount as well as the number of carboxyl group and carbon chain length of the guest anions. The intercalation isotherms of these carboxylate ions were obtained and the Freundlich isotherm equation was applicable in all cases. Furthermore, the effect of the solution pH on the intercalation was found first to be quite large and the intercalated amounts of these carboxylate ions were remarkably decreased with increasing the solution pH. The mechanism for this phenomenon was discussed in detail.
