The Syntheses of Hydrotalcite-Like Compounds and Their Structures and Physico-Chemical Properties I: The Systems Mg2+-Al3+-NO3-, Mg2+-Al3+-Cl-, Mg2+-Al3+-ClO4-, Ni2+-Al3+-Cl- and Zn2+-Al3+-Cl-

TLDR: The basic salts of this system were prepared and their structures and physico-chemical properties were studies by electron microscopy, chemical analysis, X-ray powder diffraction, thermal analysis, and acidity-basicity measurements as mentioned in this paper.

Abstract: The basic salts of this system were prepared and their structures and physico-chemical properties were studies by electron microscopy, chemical analysis, X-ray powder diffraction, thermal analysis, i.r. absorption spectra, BET absorption, and acidity-basicity measurements. The salts were found to be new compounds analogous to hydrotalcite. They can be expressed by the formula; [M 2+ M 3+ (OH)2(x+y))]y+ [A 1 − , Az2- · mH2O]-(z1 + 2z2) where M2+ and M3+ denote di- and trivalent cations, A− and A2− denote mono- and divalent anions, respectively, and y = z1 + 2z2; z1 ≫ z2. The structures consist of positively charged Cd(OH)2-like basic layers and intermediate layers formed from anions and water molecules with the solid solution of divalent cation (M2+) and trivalent cation (M3+) being formed in the range of 0.6 > x/(x + y) > 0.9. The anions of Cl−, NO 3 − and ClO 4 − are easily substituted by CO 3 2− . A large part of the NO 3 − makes a monodentate-type bond and the ClO 4 − a bridge-type bond.