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US 4,904,457 AGranted
Synthetic hydrotalcite
AssigneeAluminum Company of America
InventorChanakya Misra
Life of this patent
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Abstract
Disclosed is a method for producing hydrotalcite in high yield including reacting activated magnesia with an aqueous solution containing aluminate, carbonate, and hydroxyl ions. The method further includes a first step of heating magnesium carbonate or magnesium hydroxide to a temperature between about 500.degree.-900.degree. C. to form activated magnesia or magnesium oxide. The method is suited to producing synthetic hydrotalcite from industrial Bayer liquor.
Claims12
A method of producing hydrotalcite, comprising:
- (a) heating magnesium carbonate or magnesium hydroxide to a temperature between about 500-900.degree. C. to form activated magnesia;
- and
- (b) reacting activated magnesia with an aqueous solution of aluminate, carbonate, and hydroxyl ions at a pH above about 13 to form hydrotalcite at a conversion yield greater than about 75%.
A method of producing a material having a powder X-ray diffraction pattern of the mineral hydrotalcite comprising:
- (a) heating magnesium carbonate or magnesium hydroxide to a temperature between about 500.degree.-900.degree. C. to form activated magnesia;
- and
- (b) reacting said activated magnesia with an aqueous solution of aluminate, carbonate, and hydroxyl ions at a pH above about 13 to form hydrotalcite at a conversion yield greater than about 75%.
Dependencies are inferred from the claim text.