Producing metallic magnesium from a

Claim 1

A PROCESS FOR MANUFACTURING METALLIC MAGNESIUM BY ADDING FERROSILICON TO A MAGNESIUM OXIDE-CONTAING MATERIAL AND HEATING UNDER REDUCED PRESSURE TO EFFECT REDUCTION, WHICH COMPRISES PREPARING A MIXTURE WHICH IS SUBSTANTIALLY FREE FROM ALUMINUM, CONSISTING ESSENTIALLY OF A MAGNESIUM OXIDE-CONTAINING MATERIAL, FERROSILICON AND LIME WHEREIN, IN WHICH MIXTURE THE MOLAR RATIO OF MAGNESIUM OXIDE TO SILICON IS APPROXIMATELY 2:1 AND THAT OF CALCIUM OXIDE TO MAGNESIUM OXIDE IS ABOUT 0.26 TO 0.56, HEATING UP TO 1450*-1500*C. AND THEN RAISING THE TEMPERATURE TO 1600*C. TO EFFECT LIQUID PHASE REDUCTION, WHILE MAINTAINING A PRESSURE OF ABOUT 0.1 TO 5.0MM. HG., THEREBY FORMING MAGNESIUM VAPOR AND A MOLTEN SLAG CONSISTING OF 44 TO 64% BYH WEIGHT OF SIO2, 30 TO 53% BY WEIGHT OF CAO AND 3 TO 14% BY WEIGHT OF MGO, COOLING THE MAGNESIUM VAPOR TO RECOVER METALLIC MAGNESIUM AND SEPERATING FERROSILICON IN THE MOLTEN PHASE BY GRAVITY DIFFERENCE FROM THE MOLTEN SLAG THEREBY RECOVERING THE FERROSILICON.