Carbothermic prodn. of aluminium from aluminium oxide - giving a prod with low aluminium carbide content

摘要

Al is prepd. from an Al oxide by: striking an open electrical arc to a portion of the surface of a charge comprising an Al oxide and =1 of carbon and/or al cpds. contg. carbon; limiting the heating effect of the arc by controlling the time the arc is struck to any given portion of the surface so that the Al formed by the reaction is maintained in the liq. state with the proviso that only a small portion of the charge in the reaction zone is heated to reaction temp. while the majority of the charge is not at reaction temp. at any given time; and causing the liq. Al formed under the arc to flow away from the arc and over the non-reacted portion of the charge and be collected, the liq. Al contg. 5 wt. % of Al carbide.