| 摘要 |
A method for recovery of acids, indium, and tin from a spent ITO etching solution is provided to recover acids and effectively separate and recover indium and tin from a spent etching solution mainly containing indium and tin as a spent etching solution used for forming patterns using photolithography techniqures in fabrication process of LCD(Liquid Crystal Display) and semiconductors. A method for recovery of acids, indium, and tin from a spent ITO etching solution comprises the steps of: filtering a spent ITO(Indium Tin Oxide) etching solution to remove solid impurities therefrom; recovering acids from the filtrate using a vacuum evaporation method in which a degree of vacuum is set to a range of -520 to -540 mmHg, and temperature in a vacuum reactor is set to a range of 78 to 90 deg.C; injecting an alkali into a residual solution, thereby adjusting a pH of the residual solution to a range of 9 to 10 to precipitate and separate metallic impurities only using hydroxide; and separating and recovering indium and tin from the metallic impurity-removed purified solution by electrowinning in which a current density is set to a range of 1 to 7 mA/cm^2, and an insoluble electrode is used. The indium and tin are recovered in the form of ingot. Further, a degree of a vacuum of the vacuum evaporation method is -520 to -540 mmHg. |
