Mitsubishi Materials Corp developed a technology to recover gallium (Ga) from Ga scrap with a low cost and low environmental burden.
With the technology, Ga can be exclusively extracted without smelting all the scrap. Because the new method enables to drastically reduce the amount of chemical solution, environmental load can be reduced.
In addition, the recycled Ga can be purified with a purity of 99.99% or higher by using a technology that Mitsubishi Materials developed based on its dry and wet smelting technologies.
In general, Ga is recycled by extracting and recovering Ga after smelting all of Ga scrap with a chemical solution. In this method, metals other than Ga are also smelted, requiring a large amount of chemical solution and increasing costs and environmental load.
Ga is used for LEDs, etc as light-emitting elements such as gallium arsenide (GaAs) and gallium phosphide (GaP). Also, it is contained in CIGS (Cu-In-Ga-Se) photovoltaic (PV) cells and gallium nitride (GaN), which is a material for power semiconductors.
Currently, the global demand for Ga is about 200t per year, but it is expected to drastically increase, Mitsubishi Materials said. Japan is dependent on imports for Ga, which is produced mainly as a byproduct of zinc and aluminum refining, because it cannot produce the necessary amount of Ga domestically.