The pot material of Sb-doped n-type mono-crystal silicon was purified by our selfassembled vacuum directional solidification furnace. In the experimental, the pulling rate was 7μm/s, 10μm/s, 20μm/s, 30μm/s and 40μm/s, respectively. The experimental concentration of Sb, Al and Fe at 0.3 proportion of silicon ingot bottom to the top is detected and the theoretical concentration is calculated. The experimental results show that the pulling rate causes a great effect to concentration of Sb and a small effect to concentration of Fe. At the same time, the theoretical distribution concentration and experimental distribution concentration were compared. The experimental route provided a promising idea for complex utilization of the pot material.