Recovery of Indium from ITO Waste Solid by Electrowinning

• Main Authors: Luo,Yi-Li, 羅亦俐
• Other Authors: 蔡德華
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/e2w979

碩士 === 國立臺北科技大學 === 化學工程研究所 === 103 === This ITO waste solid is dissolve by acid solution. Before adjust this solution to pH 2, we add hydrogen peroxide oxidation to oxide Sn2+ into Sn4+. Then adding the appropriate amount of electrolyte to make the solid-liquid separation after the precipitation of impurities. Recovery of Indium from chloride solution by electrowinning, and discuss its electrolysis efficiency and metal quality¸ The electrowinning reaction are that： 2In3＋ + 6Cl－ → 2In(s) + 3Cl2 We analysis the elemental composition by using X-ray fluorescence, Atomic absorption spectrophotometer, and Energy Dispersive X-ray analysis. In this study, we have variables, such as the different anode cathode combinations, initial concentration, current density, pH of electrolyte, additive agent and electrorefinning. We observe the electrolysis efficiency, metal quality of the analysis by inductively coupled plasma optical emission spectrometry. According to the experiments, waste solid containing In, Sn, Al, Fe, Ni, Zn, Cu and Cr, We selected carbon for anode and cathode, initial concentration 9000 ppm, current density 100 A/m2 , and two-stage electrorefining to recover Indium of 4N5 purity. To make the indium plating layer of dense flat structure, add a little gelatin can be used as additives.