Recovery of platinum group metals from sulfidic raw materials

Claim 1

A PROCESS FOR THE RECOVERY OF PLATINUM GROUP METALS FROM A SULFIDE RAW MATERIAL CONTAINING IRON AND AT LEAST ONE OF THE METALS FROM THE GROUP CONSISTING OF COPPER, NICKEL AND COBALT WHICH COMPRISES AT LEAST PARTLY CONVERTING THE IRON SULFIDE INTO IRON OXIDE BY ROASTING, CONVERTING THE SULFIDES OF NON-IRON METALS OTHER THAN PLATINUM GROUP METALS INTO SOLUBLE SALTS BY ANOTHER ROASTING TREATMENT, TREATING THE ROASTED PRODUCT WITH A LIQUID TO DISSOLVE SAID SOLUBLE SALTS OF NON-IRON METALS OTHJER THAN PLATINUM GROUP METALS, SEPARATING THE IRON OXIDE-CONTAINING RESIDUE FROM THE LIQUID SOLUTION, ACTING UPON SAID RESIDUE WITH AN AQUEOUS SOLUTION OF CHLORINE TO SIMULTANEOUSLY CONVERT THE PLATINUM GROUP METALS TO THEIR WATER-SOLUBLE CHLORIDE SALTS AND DISSOLVE SAID SALTS OF THE PLATINUM GROUP METALS IN SAID AQUEOUS SOLUTION, SEPARATING THE RESIDUE FROM THE AQUEOUS SOLUTION CONTAINING THE DISSOLVED SALTS OF THE PLATINUM GROUP METALS, AND RECOVERING THE PLATINUM GROUP METALS BY PRECIPITATING THEM FROM THE AQUEOUS SOLUTION.