Recovery of rare-earth alloy particles from calcium-containing product using aqueous ammonium chloride

Claim 1

A PROCESS FOR RECOVERING RARE EARTH ALLOY PARTICLES HAVING USEFUL MAGNETIC PROPERTIES FROM A MATERIAL COMPRISED OF CALCIUM HYROXIDE, CALCIUM OXIDE AND RARE EARTH ALLOY PARTICLES, SAID CALCIUM HYDROXIDE AND CALCIUM OXIDE BEING PRESENT IN AN AMOUNT RANGING FROM ABOUT 10% TO 30% BY WEIGHT OF SAID RARE EARTH ALLOY PARTICLES, SAID RARE EARTH ALLOY PARTICLES HAVING AN AVERAGE SIZE LESS THAN 40 MICRONS AND CONSISTING ESSENTIALLY OF RARE EARTH METAL AND A METAL SELECTED FROM THE GROUP CONSISTING OF COBALT, IRON, MANGANESE AND ALLOYS THEREOF WHICH COMRISES ADMIXING SAID MATERIAL WITH AN AQUEOUS SOLUTION OF NH4CL HAVING A TEMPERATURE BELOW ROOM TEMPERATURE AND HAVING FROM 2.1 TO 3 MOLES OF NH4CL DISSOLVED THEREIN FOR EACH MOLE OF CALCIUM OXIDE AND CALCIUM HYDROXIDE PRESENT, SAID AQUEOUS SOLUTION OF NH4CL REACTING WITH AND DISSOLVING SAID CALCIUM OXIDE AND CALCIUM HYDROXIDE AND HAVING NO SIGNIFICANT EFFECT ON SAID RARE EARTH ALLOY PARTICLES, SAID REACTION HAVING NO SIGNIFICANT DETERIORATING EFFECT ON THE MAGNETIC PROPERTIES OF SAID RARE EARTH ALLOY PARTICLES, RECOVERING SAID ALLOY PARTICLES FROM THE RESULTING REACTION SOLUTION, AND DRYING SAID PARTICLES IN AN ATMOSPHERE IN WHICH THEY ARE INERT.