GB582506A - Improvements in, and relating to, the recovery of scrap metals - Google Patents

Abstract

A process for the separation, recovery or refining of metals which comprises subjecting mixtures of metals or alloys at an elevated temperature, preferably above the melting point of one or more of the constituent metals, to the action of mixtures of fuel and oxygen or an oxygen-containing gas in such a proportion that the products of combustion contain no free oxygen but hydrogen and steam and/or carbon dioxide and carbon monoxide in proportions oxidising to one or more of the constituent metals and reducing to the remainder, so as to convert one or more of the metals present into an oxide or oxides, the remainder being retained as metal and separating the oxide or oxides and the metal or metals. By this process nickel and copper may be separated from iron, preferably at a temperature between 1100 DEG C. and 1450 DEG C. and the gas mixture may be such that the products of combustion contain 7-11 per cent. of carbon dioxide, 8-1 per cent. of carbon monoxide, 10-1 per cent. of hydrogen and 15-18 per cent. of steam, the balance being substantially nitrogen. Reference is made to the separation of copper from nickel at a temperature between 1400 DEG C. and 1800 DEG C.; the separation of copper from iron at 1400 DEG C.-1500 DEG C.; the separation of lead from tin at 700 DEG C.-800 DEG C.; and the separation of iron, nickel and cobalt from aluminium at 1400 DEG C.-1500 DEG C. The spent atmosphere from these processes may be withdrawn from the furnace and oxygen or an oxygen-containing gas added in such proportions that the mixture is again suitable for selective oxidation. The material to be treated may be melted continuously in a vertical shaft furnace, with or without the addition of fluxes to convert the oxide formed to a fluid slag. The metal or alloy obtained may be transferred, molten, for final purification, to a converter or similar type of furnace, in which it is again submitted to the action of a selectively-oxidising gas mixture, with or without the addition of fluxes. Specification 9508/09, [Class 82 (i)], is referred to.