The extraction of nickel from metallurgical products

Copper ores may contain nickel which collects in the blister copper if but little arsenic is present in the ore. The nickel is obtained by subjecting the copper to a blast which gives a dross containing nickel (and cobalt), and copper with a reduced proportion of nickel. The dross, when smelted in a blast-furnace, yields a copper-nickel alloy. The treatment - blowing and smelting - of the copper-nickel alloys so obtained can be repeated until finally an alloy with the desired proportion of nickel is obtained. The dross can also be smelted with pyrites to form a nickel matte; or with barytes and arsenical pyrites to form a speiss and a copper matte; or it can be treated by a wet process.

Nickeliferous speiss obtained as a by-product in the treatment of some copper, lead, and silver ores contains nickel, and it can be worked up by a modification of the process used for extracting nickel from arsenical ores. In the refining of dross copper, and in the treatment of nickel ores, slags may be obtained which contain nickel. The slags may be smelted in a blast-furnace with pyrites or arsenical pyrites to form a matte or speiss, and treated as indicated before. The speiss may be treated for cobalt. The nickel present in iron sows may be recovered as a nickel copper alloy by treatment in a small refining hearth. The iron oxide formed by the blast is slagged with quartz. J. L. Fohlen obtained nickel matte by passing the gases from the destructive distillation of lignite over a mixture of garnierite and calcium sulphide, and recovered the hydrocarbons of low b.p. formed as a by-product.