Selenium recovery from uranium leach liquor

Claim 1

A PROCESS FOR RECOVERING URANIUM, VANADIUM AND SELENIUM VALUES FROM AN ORE WHICH COMPRISES OXIDIZING AN AQUEOUS SLURRY OF CIMMINUTED URANIUM, VANADIUM AND SELENIUM CONTAINING ORE IN THE PRESENCE OF A CARBONATE LEACHING SOLUTION IN A LEACHIN ZONE TO FORM A PREGNANT LIQUOR CONTAINNG DISSOLVED WATER SOLUBLE URANIUIMCOMPOUNDS, DISSOLVED WITH WATER SOLUBLE URANIUMCOMPOUNDS AND DISSOLVED WATER SOLUBLE SELENIUM COMPOUNDS; SEPARATING UNDISSOLVEDOLIDS; TREATING THE DISSOLVED VALUES IN SAID PREGNANT LIQUOR WITH FIRST AND SECOND AGENTS, SAID FIRST AGENT BEING SELECTED FROM THE GROUP CONSISTING OF SODIUM SULFIDE, HYDROEN SULFIDE, SODIUM THIOSULFATE, SODIUM SULFITE AND SODIUMHYDROSULFITE, AND SID SECOND AGENT COMPRISING SODIUM HYDROXIDE, SUBSTANTIALLY CONCURRENTLY TO COVERT SAID VALUES TO INSOLUBLE URANIUM, INSOLUBLE VANADIUM AND INSOLUBLE SELENIUMCOMPOUNDS; SEPARATING THE RESULTING BARREN SOLUTION FROM THE PRECIPITATED VALUES; TREATING SAID PRECIPITATED VALUES WITH AN AQUEOUS SOLUTION CONTAINING SODIUM IONS PRESENT IN AN AMOUNT RANGING FROM 5 TO 15 WEIGHT PERCENT BASED ON THE PRECIPITATED URANIUM VALUES; HEATING THE RESULTING SLURRY AT ELEVATED TEMPERATURES TO CONVERT THE SELENIUM VALUES TOSODIUM SELENITE AND VANADIUM VALUES TO SODIUM VANADATE; QUENCHING THE RESULTING HEATED PRODUCT WITH WATER TO EFFECT THE DISSOLUTION OF THE SELENIUM AND VANADIUM COMPOUNDS WHILE LEAVING THE URANIUM VALUES IN INSOLUBLE FORM; REMOVING THE VANADIUMVALUES FROM THE FIRST RESULTING SOLUTION BY CONTACTING THEREOF WITH A SOLVENT COMPRISING A QUATERNARY AMINE-HYDROCARBON MIXTURE; AND TREATING THE SECOND RESULTING SOLUTIN BY ACIDIFICATION AND REDUCTION WITH SO2 TO REDUCE SAID SELENIUMVALUES TO INSOLUBLE FORM.