Gallium

Gallium is a by-product in the processes of aluminium and zinc smelting, yet very little gallium can be obtained from sphalerite. Most of the gallium is extracted from the aluminum hydroxide solution roughly refined in the Bayer process. Sodium K-galliate is obtained through the electrolysis of mercury batteries and the hydrolysis of amalgam in sodium hydroxide, and then gallium is obtained through electrolysis. Gallium, a semiconductor, needs to be purified by zone melting technology or single crystals extracted from the molten material (i.e., the Chaser method). 99.9999% pure gallium can now be routinely obtained and is widely used in business.

Industrial production uses industrial-grade metallic gallium as raw material and further purifies it by electrolysis, vacuum distillation, stepwise crystallization and zone melting methods to obtain high-purity gallium. The electrolytic method uses industrial-grade gallium with a purity of 99.99% as raw material and, through electrolytic refining and other processes, produces high-purity gallium with a purity of ≥99.999%. Using high-purity gallium with a purity of ≥ 99.999% as raw material, it is further purified through single crystal drawing or other purification processes to obtain high-purity gallium with a purity of ≥ 99.99999%.