Process for extracting cobalt and nickel from their ores

Claim 1

IN EXTRACTING COBALT AND NICKEL VALUES FROM AN ORE THEREOF, WHICH ORE ALSO CONTAINS IRON, SULFUR AND AT LEAST ONE METALLOID SELECTED FROM ARSENIC, ANTIMONY, SELENIUM AND TELLURIUM, THE PROCESS WHICH COMPRISES THE STEPS OF: CHEMICALLY DETERMINING, FOR AN AMOUNT OR ORE TO BE TREATED, THE CONTENT TO BE DISSOLVED OF ACID-SOLUBLE, NONFERROUS METALS INCLUDING COBALT AND NICKEL, AND THE AMOUNT OF SULFUR STOICHIOMETRICALLY EQUIVALENT TO SULFATES THEREOF; FORMING WITH DILUTE AQUEOUS NITRIC ACID A FIRST SLURRY CONTAINING A SUFFICIENT AMOUNT OF IRON SULFIDE CONTAINING SOLIDS TO FURNISH ABOUT SAID DETERMINED AMOUNT OF SULFUR; AT FROM ABOUT 100* TO ABOUT 200*C. AND UNDER A POSITIVE PARTIAL OVER-PRESSURE OF OXYGEN, AGITATING SAID FIRST SLURRY UNTIL A MAJOR PORTION OF THE IRON SULFIDE CONTENT OF SAID SOLIDS IS OXIDIZED AND DISSOLVED; THEN FORMING A SECOND SLURRY CONTAINING THE RESULTANT SOLUTION, SAID AMOUNT OF ORE TO BE TREATED AND ANY REQUISITE ADDITIONAL AMOUNT OF NITRIC ACID TO FURNISH FROM ABOUT TWO TO ABOUT TWENTY PARTS OF NITRIC ACID PER HUNDRED PARTS OF SAID ORE; AND AGITATING RESULTANT SLURRY AT FRROM ABOUT 100*-200*C. UNDER A POSITIVE PARTIAL OVER-PRESSURE OF OXYGEN UNTIL DISSOLUTION OF METAL VALUES SUBSTANTIALLY CEASES.