Process for the recovery of rare earth metals from permanent magnets

Abstract

Systems and methods for recovering rare earth metals from rare earth metal-containing magnets includes fragmenting or commutating the magnets, contacting the commutated magnets with a mixture of low molecular weight carboxylic acids such as formic acid and water, and removing or extracting non-rare earth metal carboxylate phases such as an iron carboxylate (formate) phase from a rare earth metal carboxylate (formate) phase, using a solvent such as water.

1 - 10 . (canceled) 
     
     
         11 . A system comprising:
 a reaction vessel including a rare earth metal containing-magnet material input connect to a rare earth metal containing-magnet material source, a low molecular weight carboxylic acid input connected to a low molecular weight carboxylic acid source, a water input connected to a water source, a waste liquid outlet connected to a waste liquid receiver and a rare earth metal product outlet connected to a rare earth metal product receiver, where an amount of the rare earth metal containing-magnet material, the low molecular weight carboxylic acid and the water are added to the reaction vessel to form a reaction mixture and the reaction mixture is held under reaction conditions sufficient to dissolve or extract the rare earth metals to form rare earth metal carboxylates along with non-rare earth metal carboxylate hydrates that precipitate out of the reaction mixture, and   a separating vessel to separate the precipitate from the liquid and to wash the precipitate with a solvent to remove the non-rare earth metal carboxylate hydrates to form a purified rare earth carboxylate product.   
     
     
         12 . The system of  claim 11 , further comprising:
 a commutating unit to fragment the magnet material into a particulate magnet material having an average particle size between about 10 nm and about 5 nm.   
     
     
         13 . The system of  claim 11 , wherein the low molecular weight carboxylic acid is formic acid a magnet material to formic acid to water ratio is between about 1.0:1.0:20 w/w to about 1.0:2.0:50 w/w. 
     
     
         14 . The system of  claim 13 , wherein the magnet material to formic acid to water ratio is between about 1:1.2:20 w/w/ and about 1:1.8:50 w/w. 
     
     
         15 . The system of  claim 14 , wherein the magnet material to formic acid to water ratio is between about 1.0:1.4:20 w/w and about 1.0:1.5:40 w/w. 
     
     
         16 . The system of  claim 15 , wherein the magnet material to formic acid to water ratio is about 1:1.44:30 w/w. 
     
     
         17 . The system of  claim 11 , wherein the reaction conditions include at least a reaction temperature, a reaction pressure, a reaction time, and a stirring rate. 
     
     
         18 . The system of  claim 17 , wherein:
 the reaction temperature is between about 25° C. and about 120° C.,   the reaction pressure is between about 1 atmosphere and about 5 atmospheres,   the reaction time is at least 24 hours, and   the rate stirring is at least 500 rpm.   
     
     
         19 . The system of  claim 18 , wherein:
 the reaction temperature is any discrete temperature in the range between about 25° C. and about 120° C.,   the pressure is ambient pressure,   the reaction time is any discrete time period in the range between 3 hours and 24 hours, and   the stirring rates is any discrete stirring rate in the range between 100 rpm and 500 rpm.   
     
     
         20 . (canceled)