Process for the recovery of copper from its ores and minerals

Claim 1

AN IMPROVED PROCESS FOR TREATING A COPPERBEARING SOLIDS MIXTURE, AT LEAST A PART OF WHICH COMPRISES SULFIEDES OF COPPER AND OF IRON FOR EFFECWHICH THE COPPER-IRON RATIO IS TOO LOW FOR EFFECTIVE RECOVERY OF COPPER BY DIRECT ACID LEACHING, TO DISSOLVE AND RECOVER THE COPPER CONTENT THEREOF WHILE ELIMINATING IRON, WHICH PROCES COMPRISES: ADMIXING A PORTION OF SAID SOLIDS MIXTURE WITH A VOLUME OF AQUEOUS SULFURIC ACID TREATING LIQUOR CONTAINING COPPER IONS, SAID PORTION OF SOLIDS HAVING AN IRON CONTENT CHEMICALLY EQUIVALENT TO AT LEAST A MAJOR PORTION OF THE DISSOLVED COPPER IN SAID LIQUOR; CONTINUING THE TREATMENT OF SAID SOLIDS WITH SAID VOLUME OF LIQUID UNTIL PRECIPITATION OF COPPER FROM SOLUTION AS COPPER SULFIDE WITH THE CONCOMITANT SOLUTION OF A CHEMICAL EQUIVALENT OF IRON AS FERROUS SULFATE SUBSTANTIALLY CEASES, SAID VOLUME OF LIQUOR BEING AT LEAST SUFFICIENT FOR ITS COPPER CONTENT, TO PRODUCE IN THE SOLID RESIDUE A COPPER-IRON RATIO APPRECIABLY GREATER THAN UNITY; FILTERING THE TREATED MIXTURE; REMOVING THE FERROUS SULFATE-CONTAINING FILTRATE FROM THE CIRCUIT; TREATING THE RESULTANT COPPERSULFIDE-ENRICHED PRESSCAKE BY GASEOUS OXIDATION IN THE PRESENCE OF AQUEOUS SULFURIC, WHEREBY THE COPPER AND IRON CONTENT THEREOF IS CONVERTED TO A SOLUTION OF DISSOLVED SULFATES; REMOVING COPPER FROM SAID SOLUTION IN AMOUNT SUBSTANTIALLY EQUIVALENT TO THE COPPER AND RETURNING THE RESIDUAL TION OF SAID SOLIDS AND RETURNING THE RESIDUAL COPPER BEARING LIQUOR AS TREATING LIQUOR FOR AN ADDITION PORTION OF SOLIDS MIXTRE.