ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

New components in the electrolyte of aluminum furnaces

A. I. Belyaev

M. I. Kalinin Sci. Research Inst. Non-Ferrous Metals and Gold, Moscow.

Abstract: The temp. of primary redn. can be decreased by the addn. of AlF₃, CaF₂, and MgF₂, already used commercially, and by BaF2, BeF2, LiF, NaCl, and BaCl₂. K salts cannot he used because they destroy the bottom of the furnace. The d. of the electrolyte is decreased by AlF₃, NaCl, BeF₂, and LiF and increased by MgF₂, CaF_2, and BaCl₂. Viscosity is decreased by NaCl. Elec cond. is increased by LiF, NaCl, and BaCl₂ and decreased by the other salts. The interfacial tension at the dividing line of fused Al and electrolyte is higher the lower the soly. of Al in the electrolyte. The most effective salts are BeF₂, AlF₃, and MgF₂. AlF₃ and MgF₂ have proved their value under com. production conditions. In cryolite-Al₂O₃ melts, Al losses are decreased by increasing the generalized moment of the cation of the added salt. BeF₂ and MgF₂ slightly increase the Al losses because they assist the formation of Al⁺ in the electrolyte. Decrease of the temp. of primary redn. of the electrolyte increases the thermal losses. Increase of the elec. cond. decreases power losses in the electrolyte. The increase in current yield is caused by such salts which increase either the elec. cond. or the interfacial tension between fused Al and electrolyte.

Full paper in Portable Document Format: 1311a699.pdf (in Russian)

Chemical Papers 13 (11) 699–710 (1959)