Purification of metal halides

Claim 1

A METHOD FOR PURIFYING AN IMPURE METAL TETRAHALIDE SELECTED FROM THE GROUP CONSISITNG OF ZIRCONIUM TETRAHALIDE, HAFNIUM TETRAHALIDE, AND MIXTURES THEREOF WHICH COMPRISES THE FOLLOWING SEQUENTIAL STEPS (1) FORMING IN A MELTER A MOLTEN MIXTURE COMPIRSING ABOUT 70 TO 90 WEIGHT PERCENT OF SAID IMPURE METAL TETRAHALIDE AND ABOUT 10 TO 30 WEIGHT PERCENT OF AT LEAST ONE ALKALI METAL HALIDE, (2) HEATING SAID MOLTEN MIXTURE IN SAID MELTER TO A TEMPERATURE WITHIN THE RANGE OF ABOUT 550* TO 650* F. TO REMOVE GASEOUS IMPURITIES THEREFROM AND SEPARATING THE GASEOUS INPURITIES FROM SAID MOLTEN MIXTURE, SAID MOLTEN MIXTURE CONTAINING A MINOR AMOUNT OF FINELY DIVIDED METAL SELECTED FROM THE GROUP CONSISTING OF ZIRCONIUM AND HAFNIUM, (3) PASSING THE THUS TREATED MOLTEN MIXTURE FROM SAID MELTER TO SPEARATE AND DISTINCT VAPORIZER, (4) HEATING THE THUS TREATED MOLTEN MIXTURE AT A TEMPERATURE AT LEAST AS HIGH AS THAT AT WHICH THE METAL TETRAHALIDE IS VAPORIZED THEREFROM, (5) RECOVERING SIAD EVOLVED PURFIED METAL TETRAHALIDE, (6) RECYCLING THE MOLTEN MIXTURE FROM WHICH SAID METAL TETRAHALIDE HAS BEEN VAPORIZED FROM SAID VAPORIZER BACK TO SAID MELTER, AND (7) ADDING TO SAID MOLTEN MIXTURE IN SAID MELTER IMPURE METAL TETRAHALIDE AT SUBSTANTIALLY THE SAME RATE AT WHICH THE PURFIED METAL TETREAHALIDE IS BEING RECOVERED.

Claim 2

A METHOD FOR PURIFYING AN IMPURE METAL TETRAHALIDE SELECTED FROM THE GROUP CONSISITNG OF ZIRCONIUM TETRAHALIDE, HAFNIUM TETRAHALIDE, AND MIXTURES THEREOF WHICH COMPRISES THE FOLLOWING SEQUENTIAL STEPS (1) FORMING IN A MELTER A MOLTEN MIXTURE COMPIRSING ABOUT 70 TO 90 WEIGHT PERCENT OF SAID IMPURE METAL TETRAHALIDE AND ABOUT 10 TO 30 WEIGHT PERCENT OF AT LEAST ONE ALKALI METAL HALIDE, (2) HEATING SAID MOLTEN MIXTURE IN SAID MELTER TO A TEMPERATURE WITHIN THE RANGE OF ABOUT 550* TO 650* F. TO REMOVE GASEOUS IMPURITIES THEREFROM AND SEPARATING THE GASEOUS INPURITIES FROM SAID MOLTEN MIXTURE, SAID MOLTEN MIXTURE CONTAINING A MINOR AMOUNT OF FINELY DIVIDED METAL SELECTED FROM THE GROUP CONSISTING OF ZIRCONIUM AND HAFNIUM, (3) PASSING THE THUS TREATED MOLTEN MIXTURE FROM SAID MELTER TO SPEARATE AND DISTINCT VAPORIZER, (4) HEATING THE THUS TREATED MOLTEN MIXTURE AT A TEMPERATURE AT LEAST AS HIGH AS THAT AT WHICH THE METAL TETRAHALIDE IS VAPORIZED THEREFROM, (5) RECOVERING SIAD EVOLVED PURFIED METAL TETRAHALIDE, (6) RECYCLING THE MOLTEN MIXTURE FROM WHICH SAID METAL TETRAHALIDE HAS BEEN VAPORIZED FROM SAID VAPORIZER BACK TO SAID MELTER, AND (7) ADDING TO SAID MOLTEN MIXTURE IN SAID MELTER IMPURE METAL TETRAHALIDE AT SUBSTANTIALLY THE SAME RATE AT WHICH THE PURFIED METAL TETREAHALIDE IS BEING RECOVERED.