| 摘要 |
<p>A synthetic hydrotalcite comprises the general formula M(II)xM(III)yM'(III)z(OH)aAâ cH20 or M(II)xM(III)yM(IV)z(OH)aAâ cH20, wherein; 0â ¤zâ ¤yâ ¤xâ m6, a>x>c>b; M(II) is a divalent cation selected from; Mg, Zn, Cu, Co, Fe and Ni; M(III) is at least one trivalent cation selected from Al, Mn, Co, Ga, La, Ce and Ti; M(IV) can be Zr or Ti; A defines an anion which compensates the positive charge of the brucite type layers and can be at least one of the following: carbonate, nitrate, sulphate, chloride, hydroxide and phosphate. The synthetic hydrotalcite may have a partial CO2 capacity greater than 5 wt%. A method of forming the synthetic hydrotalcite is comprises the following steps: a. preparation of a solution by mixing the metallic precursors other than carbonates to generate concentrations up to 3M; b. addition of a solution of an hydroxide and carbonate of an alkali element, said II having concentrations up to 10M, until the pH less than 12, at temperatures up to 70°C; and one or more of the following steps: c. filtration; d. washing; e. hydrothermal treatment; f. milling; g. drying; h. calcination.</p> |
