| 摘要 |
PCT No. PCT/US96/07514 Sec. 371 Date Nov. 10, 1997 Sec. 102(e) Date Nov. 10, 1997 PCT Filed May 23, 1996 PCT Pub. No. WO96/37637 PCT Pub. Date Nov. 28, 1996A method of producing aluminum, comprising the steps of: a) providing an aluminum reduction Hall cell for reduction of alumina in molten fluoride electrolyte containing cryolite, the cell comprising a cathode, an anode and a sidewall, the sidewall having a thickness and comprising: i) a lining consisting essentially of a material selected from the group consisting of silicon nitride, silicon carbide, and boron carbide, and having a density of at least 95% of theoretical density, and no apparent porosity, and ii) an insulating layer backing the lining, b) contacting the lining with an electrolyte comprising at least 60% cryolite and having a temperature of between 650 DEG C. and 1100 DEG C., and c) providing an electric current from the cathode to the anode through the electrolyte, thereby producing aluminum at the cathode, wherein the electrolyte temperature, the cryolite concentration and the thickness of the sidewall are predetermined so that the cryolite does not form a frozen crust anywhere on the lining.
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