Precipitation of pure metallic copper from copper-bearing solutions

Claim 1

IN PROCESS OF RECOVERING COPPER IN HIGH PURITY FROM SOLID COPPER-BEARING MATERIAL WHEREIN SAID MATERIAL IS TREATED BY "SOLUTION OPERATIONS" TO OBTAIN A SOLUTION CONTAINING CUPRIC AND CUPROUS IONS AND COPPER METAL IS CHEMICALLY PRECIPITATED FROM RESULTANT SOLUTION, THE IMPROVEMENT WHICH COMPRISES: CONTACTING ADDITIONAL COPPER METAL WITH SAID SOLUTION AND AT BELOW 100* C., SUBSTANTIALLY SATURATING THE LIQUID WITH CARBON MONOXIDE, WHEREBY ADDITIONAL COPPER IS INTRODUCED INTO SOLUTION WITH A CONCURRENT EQUIVALENT REDUCTION OF CUPRIC TO CUPROUS IONS; SUBJECTING SO-TREATED LIQUOR, AT A PRESSURE OF FROM ABOUT 75 TO ABOUT 1000 POUNDS PER SQUARE INCH AND AT LEAST SUFFICIENT TO PREVENT BOILING OF THE SOLUTION AND UNDER AN ATMOSPHERE COMPRISING CARBON MONOXIDE TO A TEMPERATURE ABOVE 100* C., BUT NOT MORE THAN 150* C. FOR AMMONIACAL LIQUORS AND 300*. FOR ACID LIQUORS, FOR SUFFICIENT TIME TO PRECIPITATE AT LEAST AN AMOUNT OF COPPER METAL POWDER GREATER THAN THAT DISSOLVED IN REDUCING CUPRIC TO CUPROUS IONS, BUT NOT MORE THAN SO MUCH AS IS AT LEAST 99.9% CIPPER; COLLECTING PREIPITATED COPPER AND RECIRCULATING RESIDUAL COPPER TO THE "SOLUTION OPERATIONS".