The invention relates to an ultra-pure aluminum purification
crystallization method. The method comprises the following steps that an aluminum
raw material of which the purity is 3-5N is melted into molten aluminum in a
crucible; a
crystallization device is installed on the upper portion of the
crucible, the lower end of the
crystallization device stretches into the surface of the molten aluminum,and normal-temperature air at 50-100L / min is continuously injected into the crystallization device through an air feeding
pipe arranged at the upper end of the crystallization device; a motor is started to drive the crystallization device to rotate continuously, the rotation speed of the motor is increased, it is kept that the surface of the molten aluminum is not influenced, high-purity part ofthe molten aluminum solidifies and stacks at the lower end of the crystallization device and forms a
crystal substance; when the size of the
crystal substance reaches half of the set size, the crystallization device is taken out and stopped rotating, the lower end of the crystallization device and the
crystal substance are quickly cooled in the air to 280-320 DEG C, then, the crystallization device is inserted into the molten aluminum to continue rotating till the crystal substance cannot be increased, and the crystal substance is taken down; and 50-70 mm portions of the head and
tail of the crystal substance are
cut off, and a preliminary purification substance is obtained. The ultra-pure aluminum purification crystallization method is simpler and more efficient in technology, more practical, and more suitable for industrial production.