2017 Volume 69 Issue 10 Pages 485-490
The amount of light-emitting-diodes（LEDs）using gallium（Ga）for lighting unit is now increasing and the amount of disposal of lighting unit using LEDs is also increasing. It is important to establish a recovery method of Ga from used LEDs, because Ga is regarded as rare metals. It is known that Ga compounds are vaporized in a high temperature reducing atmosphere. Using this reaction, we proposed a method to deposit the vaporized Ga compound on a heat resistant plate with moderate gas permeability. In this research, the optimum reaction conditions were examined and the mechanism of recovery of Ga was investigated. As a result, we showed that it is possible to recover the Ga compound in a yield of about 16% by vaporizing the Ga compound.
