Method of separating rare earth metal ions

Claim 1

A PROCESS FOR SEPERATING THE RARE EARTH METAL VALUES OF SALTS OF YTTRIUM GADOLINIUM FROM A PLURALITY OF IONIZABLE SALTS OF RARE EARTH METALS AND FROM SALTS OF ONE ANOTHER CONTAINED IN AN AQUEOUS SOLUTION, WHICH PROCESS COMPRISES FEEDING AN AQUEOUS SOLUTION CONTAINING IONIZABLE SALTS OF A PLURALITY A RARE EARTH METAL VALUES CONSISTING OF A PREDOMINANT AMOUNT OF AT LEAST ONE OF THE RARE EARTH METALS YTTRIUM AND GADOLINIUM INTO CONTACT WITH A BED OF THE HYDROGEN FROM A CATION EXCHANGE RESIN CONTAINING SULFONIC ACID GROUPS AS THE ACTIVE GROUP OF THE RESIN, WHEREBY THE RARE EARTH METAL VALUES ARE SORBED ON THE CATION EXCHANGE RESIN, THEN FEEDING TO THE BED AN AQUEOUS ELUANT SOLUTION CONSISTING OF FROM 0.01 TO 0.1 MOLEAR SOLUTION OF AN ALKALI SALT OF DIETHYLENETRIC AMINE PENTA ACETIC ACID SELECTED FROM THE GROUP CONSISTING OF THE AMMONIUM, SODIUM, POTASSIUM AND LITHIUM SALTS OF DIETHYLENETRIAMINE PENTA ACETIC ACID HAVING AN AVERAGE OF FROM 2.5 TO 3.5 OF THE ACETIC ACID GROUPS IN THE FORM OF SAID ALKALI SALT AND HAVING A PH VALUE BETWEEN 5.0 AND 8.5, THEREBY SELECTIVELY ELUTING THE ABSORBED RARE EARTH METAL VALUES FROM THE RESIN, AND COLLECTING SUCCESSIVE FRACTIONS OF THE EFFLUENT LIQUID WHICH CONTAINS THE YTTRIUM AND GADOLINIUM METAL VALUES SEPARATED FROM THE OTHER RARE EARTH METAL VALUES AND FROM ONE ANOTHER AND RECOVERING THEYTTRIUM AND GADOLINIUM METAL VALUES FROM THE SEPARATED FRACTIONS OF THE EFFLUENT LIQUID.