Effect of Silicon Separation on the Preparation of High-Purity Aluminum

To evaluate the effect of the distribution coefficient (kSi) on silicon (Si) separation during aluminum (Al) refining by zone melting, kSi is measured under different experimental conditions, and the obtained samples are examined. The experimental results show that Si content in the sample located in the middle region is less than 2.33 ppm (Its location number is No. 3) when the zone melting speed is less than 1 mm/min. As the times of purification increasing, kSi gradually approaches k0, and the migration effect of Si is significantly improved. The influence of the times of purification on the distribution coefficient is obviously greater than that of the zone melting speed. When the zone melting speed is 1 mm/min, and there are 10 and 15 times, the highest removal rate of Si occurs in the middle of the sample. The Si removal rates in the samples at No. 3 are 74% and 74.6%, respectively.