Magnesium aluminum hydrotalcite and method for preparing magnesium aluminum hydrotalcite

The present invention relates to the field of the hydrotalcite, discloses magnesium aluminum hydrotalcite and a method for preparing the magnesium aluminum hydrotalcite, the method comprises the following steps: (1) in the presence of water, performing ball-milling on a magnesium source and / or aluminum hydroxide to obtain a sol precursor; (2) diluting the sol precursor with water, mixing the diluted solution with the magnesium source and / or aluminum hydroxide, contacting the obtained mixture with an acid matter, and thermally insulating at 30-90 DEG C for 10-300min to obtain a magnesium aluminum composite sol; (3) under hydrothermal reaction conditions, contacting the magnesium aluminum composite sol with a crystal form control agent to obtain magnesium aluminum hydrotalcite paste; and (4) contacting the magnesium aluminum hydrotalcite paste with a surface modification agent for reaction. The method has the advantages of simple process and low cost, and can improve the crystallinity of the magnesium aluminum hydrotalcite.