Treatment of lateritic ores

Claim 1

A METHOD FOR TREATING LATERITIC ORES HAVING THE FOLLOWING COMPOSITION OF METALS IN APPROXIMATE PERCENTAGE BY WEIGHT: IRON, 25-35%; MAGNESIUM, 5-15%; NICKEL, 0.8-1.50%; COBALT, 0.10-0.15%; AND CHROMIUM 2.003.50%; WHICH COMPRISES, AS A FIRST CHEMICAL TREATMENT STEP, LEACHING THE ORE WITH A STOICHIOMETRIC EXCESS, BASED ON THE METAL VALUES, OF A SULFURIC ACID SOLUTION CONTAIING BETWEEN ABOUT 25 AND 50% BY WEIGHT SULFURIC ACID TO PRODUCE AN ACID LEACHED PULP AND AN ACID LEACHED SOLUTION CONTAINING SUBSTANTIALLY ALL THE METAL VALUES IRON, MAGNESIUM, NICKEL AND COBALT; SEPARATING THE ACID LEACHED PULP FROM THE ACID LEACHED SOLUTION; DRYING THE ACID LEACHED SOLUTION TO PRODUCE AN ACID LEACHED SOLUTION RESIDUE; ROASTING THE CID LEACHED SOLUTION RESIDUE AT A TEMPERATURE OF BETWEEN 975* AND 1050*F. AND RECOVERING OVERHEAD VOLATILIZED SULPHURIC ACID AND EVOLVED SULPHUR OXIDE; WATER-LEACHING THE ROASTED RESIDUE; SEPARATING THE INSOLUBLE FERRIC OXIDE FROM THE WATER LEACHED SOLUTION; AND ELECTROLYZING THE WATER LEACHED SOLUTION TO SEPARATE THE NICKEL AND COBALT FROM SAID WATER LEACHED SOLUTION.

Claim 2

A METHOD FOR TREATING LATERITIC ORES HAVING THE FOLLOWING COMPOSITION OF METALS IN APPROXIMATE PERCENTAGE BY WEIGHT: IRON, 25-35%; MAGNESIUM, 5-15%; NICKEL, 0.8-1.50%; COBALT, 0.10-0.15%; AND CHROMIUM 2.003.50%; WHICH COMPRISES, AS A FIRST CHEMICAL TREATMENT STEP, LEACHING THE ORE WITH A STOICHIOMETRIC EXCESS, BASED ON THE METAL VALUES, OF A SULFURIC ACID SOLUTION CONTAIING BETWEEN ABOUT 25 AND 50% BY WEIGHT SULFURIC ACID TO PRODUCE AN ACID LEACHED PULP AND AN ACID LEACHED SOLUTION CONTAINING SUBSTANTIALLY ALL THE METAL VALUES IRON, MAGNESIUM, NICKEL AND COBALT; SEPARATING THE ACID LEACHED PULP FROM THE ACID LEACHED SOLUTION; DRYING THE ACID LEACHED SOLUTION TO PRODUCE AN ACID LEACHED SOLUTION RESIDUE; ROASTING THE CID LEACHED SOLUTION RESIDUE AT A TEMPERATURE OF BETWEEN 975* AND 1050*F. AND RECOVERING OVERHEAD VOLATILIZED SULPHURIC ACID AND EVOLVED SULPHUR OXIDE; WATER-LEACHING THE ROASTED RESIDUE; SEPARATING THE INSOLUBLE FERRIC OXIDE FROM THE WATER LEACHED SOLUTION; AND ELECTROLYZING THE WATER LEACHED SOLUTION TO SEPARATE THE NICKEL AND COBALT FROM SAID WATER LEACHED SOLUTION.