ALUMINUM RAW MATERIALS FOR ALUMINUM REFINING, MELTING METHODS FOR REFINING SUCH ALUMINUM AND PREPARING REINALUMINIUM MATERIAL THEREFOR FOR ELECTROLYTE CONDENSER ELECTRODES

摘要

As a raw material for refining, a raw material for aluminum refining is used, wherein the raw material contains a peritectic element and boron, the amount of boron being contained excessively by 5 to 80 mass ppm to a total chemical equivalent calculated as a metal boride with the peritectic element. In a melting furnace 1, the raw material for aluminum refining is melted into a molten metal. In a reaction chamber 2A, a metal boride is formed by reacting the peritectic element with boron in the molten metal, and the formed metal boride and the metal boride formed during the melting step are removed. Furthermore, in refining chambers 2B, 2C, 2D and 2E, a high purity aluminum from which an eutectic element containing unreacted boron is crystallized by segregation solidification.