DE2037018

1290056 Recovering metals from alloy scrap SHERRITT GORDON MINES Ltd 8 June 1970 [20 Nov 1969] 27661/70 Heading C7D Ni and other non-ferrous metals such as Co and Cu are recovered from Ni, Fe and Cr containing alloy scrap by melting the alloy scrap and adding thereto, preferably 3 to 12% by weight, sulphur e.g. as pyrite, atomizing the S-containing melt e. g. using water jets to produce solid granules containing matte, heating the granules e. g. at 425-925‹ C. for up to 2 hours to increase their grindability, then grinding and leaching e. g. in aqueous ammoniacal ammonium sulphate, or sulphuric acid solution under a partial pressure of oxygen of 15-30 psi and at 120-127‹ C., to extract Ni and any Co and Cu. The alloy scrap may contain other metals such as Mn, Mo and W which, with Fe and Cr, remain in the leach residue. The granules may be heated in a reducing, oxidizing or neutral atmosphere, e.g. H 2 , air or N 2 , in a rotary kiln, muffle, crucible or retort furnace.