| 摘要 |
1295117 Anode for aluminium extraction SWISS ALUMINIUM Ltd 26 Nov 1970 [5 Dec 1969] 56268/70 Heading C7B In the extraction of aluminium from a fused alumina-containing bath of alkali aluminium fluoride, the part of the anode which contacts the electrolyte comprises an oxidic electron conducting ceramic material chemically resistant to the electrolyte. Preferably the material contains at least 80% SnO 2 together with one or more of Fe 2 O 3 , ZnO, Cr 2 O 3 and one or more of Ta 2 O 5 , Sb 2 O 3 , Nb 2 O 5 and WO 5 . The anode normally comprises a closed tube 12 made of the ceramic material. Fig.2 shows three ways by which the anode may be connected to the current supply. In the left hand tube a titanium carbide rod 14 projects into a pool of molten silver 13. The middle tube is coated with a thin layer of silver or platinum and a hollow cylinder 15 of nickel alloy wire mesh is inserted to make contact with the coating. In the right hand tube a rod of zirconium diboride 18 is used to contact nickel powder 17. |
