Patent ID: 7964175
Filing Date: 2011-06-21
Classification: B01D,B01J,C01B,C01G,C01P,Y02P

Abstract:
1. A process for obtaining mixed multimetallic oxides containing laminar metallic hydrotalcite type compounds, wherein the laminar metallic hydrotalcite type compounds include four metallic cations, forming part of sheets of the hydrotalcite type compounds represented by the following formula: [M(II)+M(II)′]/[(M(III)+M(III)′], is the molar relationship between divalent cations and trivalent cations, and is between 0.5 and 10; M(II) represents an element of group 2, 6-12 of the periodic table with a valence equal to two; M(II)′ represents an element of group 2, 6-12 of the periodic table with a valence equal to two or three, which can be the same as M(II) but with different valence; M(III) represents an element of group 4-8, 13 with a valence equal to 3 and different from M(II) and M(II)′; M(III)′ represents an element of group 4-8, 13 with a valence equal to 3 and different from M(II) and M(III) or the same as M(III) but with a different valence; at least one of M(III) and M(III)′ is Al A, represents an interlaminar anion located between the sheets; n−, represents the negative electronic charge of the interlaminar anion, and may be from −1 to −8); x=0.01 up to 0.99; y=0.01 up to 0.99; and z=0.01 up to 0.99; the process for preparation of the multimetallic hydrotalcites comprising: (1) preparing an aqueous or organic solution containing three or more cations from precursor compounds selected from the group consisting of oxides, hydroxides, chlorides, nitrates, acetates and mixtures thereof; (2) preparing an alkaline solution of 0.5 to 10 molarity from at least one selected from the group consisting of KOH, K (3) slowly combining solutions (1) and (2) to cause co-precipitation of the cations at a pH between 7 and 12 at a temperature between 293 and 373 K to obtain a precipitate containing hydrotalcites; (4) washing the precipitate containing the hydrotalcites with water to remove non-precipitated ions; and (5) drying the precipitate between 333 and 473K in an atmosphere selected from the group consisting of air, oxygen, nitrogen, under vacuum, or mixtures thereof.