Two powder synthesis of hydrotalcite and hydrotalcite-like compounds

Abstract From the Canadian patent

There is provided an improved method for making synthetic hydrotalcite by first reacting powdered magnesium oxide with a high surface area, transition alumina in a solution or suspension to form a meixnerite-like intermediate. This intermediate is then contacted with an anion source such as an acid, and most preferably carbon dioxide to form , the layered double hydroxide which is separated from the suspension by filtering, centrifugation vacuum dehydration or other known , means. On a preferred basis the transition alumina combined , with activated magnesia consists essentially of a rehydratable alumina powder having a surface area of 100 m2/g or greater. To make related double …