Patent ID: 7807128

Claim:
A process for obtaining multimetallic anionic clays (MACs) characterized in that the laminar metallic hydroxides obtained are constituted of three or more metallic cations, forming part of the anionic clay's layers and have the following formula: [M(II) 1−x M(III) x (OH) 2 ](A n− x/n ).m H 2 O, where [M(II)]/[(M(III)], is the molar ratio between the divalent cations and the trivalent cations and is 0.5-10; M(II) represents one or a combination of two or more elements from group 2, 6-12 and 14 on the periodic table with valence equal to two; M(III) represents a combination of two or more elements from group 4-9, 13, Ce, and La, with valence equal to 3 and being different from M(II), A represents an anion located between the layers composed of the aforementioned cations, n− represents the interlaminar anion's negative electronic charge and may be from −1 to 8, m represents the water molecules present as hydration water or as water present in the interlaminar region and can be from 0-2, x=0.09 to 0.67, said process comprising: a) dissolving one, two, or more water-soluble divalent and/or trivalent metal precursors in water, maintaining control over the water/solid weight ratio, b) admixing one, two, or more water-insoluble divalent and/or trivalent metal precursors in powder form or in water suspension form, or a combination of both, with solution (a) to form a reaction mixture, and disperse insoluble particles of said water-insoluble precursor in said reaction mixture, wherein the reaction mixture is an aqueous mixture of said water-soluble divalent and/or trivalent metal precursors and said water-insoluble divalent and/or trivalent metal precursors, c) aging the reaction mixture slurry at temperatures between 0-100° C., for 0.1 hour to 10 days, at atmospheric pressure or in an autoclave at temperatures between 100-300° C., at pressures greater than atmospheric pressure for 0.1 hour to 10 days, said slurry having a pH in the range of 6 to 12, d) drying the slurry at a temperature between 60 and 250° C., with air, nitrogen, or a vacuum, or any combination thereof.