Recovery of Gallium from Gallium Nitride-containing Light-Emitting Diode Waste Wafer

• Main Authors: Li-LinHsu, 許立霖
• Other Authors: Wei-Sheng Chen
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/26sbpq

碩士 === 國立成功大學 === 資源工程學系 === 107 === In this study, the separation and purification of gallium were used by hydrometallurgy from gallium nitride-containing light-emitting diode (blue LED) waste wafer for the LED industry. The experiment was divided into four parts, characterization of waste wafers, acid leaching, metal separation and precipitation. Finally, a product was obtained that can be returned to the industry.Firstly, the characteristics analysis of the waste wafer were analyzed, and the results of the analysis were used as the basis for the leaching experiment. In the leaching section disscussed the effect of different leaching methods on the leaching efficiency of gallium. The results show that the use of optimal parameters for pressurized acid leaching ,the leaching efficiency of gallium was up to 99.5%.In metal separation, the batch experiments were first carried out by using IRA-200C, IRC-748 and XAD-2 ion exchange resin.Then IRA-200C and IRC-748 resin were used for adsorption and desorption of column experiments. Finally, IRC-748 ion exchange resin was selected to adsorb gallium at pH=5 in leaching solution, and the adsorption efficiency of gallium was more than 99.5%. The use of sulfuric acid as desorbing agent which could separate gallium ions from the resin effectively with desorption efficiency more than 99.5%.The research of metal product precipitation used sodium hydroxide to adjust the pH value of the desorption solution, and calcined by high temperature. The product of gallium dioxide was obtained and the purity of the product was about 99%. The recovery rate of gallium is more than 99%.