Patent ID: 8152895

Claim:
A process of producing magnesium metal comprising: (a) reacting a magnesium silicate with a caustic material to produce magnesium hydroxide; (b) reacting carbon dioxide with an alkali-metal silicate to produce silica and alkali-metal bicarbonate; (c) reacting the alkali-metal bicarbonate with the magnesium hydroxide to produce alkali-metal carbonate and magnesium carbonate; (d) reacting the alkali-metal carbonate with an alkaline-earth metal hydroxide to form a carbonate of the alkaline-earth metal and a caustic hydroxide of the alkali metal; (e) calcining the alkaline-earth metal carbonate to form an oxide of the alkaline-earth metal and carbon dioxide; (f) reacting the alkaline-earth metal oxide with water to substantially regenerate the alkaline-earth metal hydroxide consumed in step (d); and (g) reacting the magnesium carbonate from step (c) in one or more reaction steps to produce magnesium metal.