GB340497A - - Google Patents

Abstract

340,497. Refining copper. ELECTRICAL RESEARCH PRODUCTS, Inc., 195, Broadway, New York, U.S.A.-(Assignees of Harris, J. E. ; 102, Oakland Terrace, Newark, and White, J. H. ; 20, Burchfield Avenue, Cranford, both in New Jersey, U.S.A.) Sept. 30, 1929, No. 29582. Convention date, March 8. [Class 82 (i).] Copper of high electrical conductivity which may be heated in a reducing atmosphere without becoming embrittled is produced by keeping molten pure copper in a vessel lined with a refractory material which is capable of preventing the vessel from giving up to the copper small portions of impurities and adding a deoxidizing agent. The lining may be a substantially pure oxide which is not readily reducible and which adheres to the vessel at the temperature of molten copper. In an example, a crucible 2, made of a mixture of fireclay and graphite, together with its lid 4, is lined with aluminium oxide, partially filled with commercially pure electrolytic copper and placed in an electric furnace 1. 0À1 per cent of calcium boride, preferably in crystalline form, is added just before pouring. Magnesium oxide may be used as a lining and the process may be carried out in a ladle. Reference has been directed by the Comptroller to Specification 16307/13, [Class 82 (i), Metals, Extracting &c.].