Selective sulfation process for partitioning ferrous and non- ferrous values in an ore

摘要

Process for quantitatively converting non-ferrous metals chosen from the group consisting of copper, nickel, cobalt, vanadium, and manganese in an ore concentrate to soluble sulfates and simultaneously convert the ferrous values in the ore to insoluble oxides. The process comprises roasting finely divided ore particles at a temperature in excess of 650. degree. C. in the presence of a roaster gas comprising at least a stoichiometric amount of oxygen and at least 1% SO.sub.2. The roasting is performed in the presence of a sufficient amount of a mixture of salts to allow the formation of a liquid coating on the ore particles. In a preferred embodiment, the mixed salt which forms the liquid coating comprises Na.sub.2 SO.sub.4 and K.sub.2 SO.sub.4 with the ratio of sodium to potassium being between 1.0 and 2.0.