화학공학소재연구정보센터
KAGAKU KOGAKU RONBUNSHU, Vol.34, No.2, 282-286, 2008
Recovery of Indium from Spent Panel of Liquid Crystal Display Panels
Fundamental research was conducted on the recovery, separation and purification of indium from spent liquid crystal display panels containing a small amount of indium. Acid leaching tests suggested that effective extraction can be achieved by using hydrochloric acid, with nearly the same efficiency as aqua regia. Solvent extraction tests suggested that indium can be effectively extracted with trialkylphosphine oxide compounds from concentrated hydrochloric acid. High porous XRD-7 resins impregnated with Cyanex 923 and Aliquat 336 were prepared to examine their adsorption behaviors from hydrochloric acid for all metal ions contained in the spent panels. The two types of resins were packed in two columns, through which model hydrochloric acid solution containing the same concentrations of metal ions as those in the each liquor was passed. In the first column, in which the resin impregnated with Aliquat 336 was packed, the major impurities, iron, tin and zinc, were removed. In the second column in which the resin impregnated with Cyanex 923 was packed, indium was selectively adsorbed. The loaded indium was eluted with dilute sulfuric acid and was enriched more than 10 times composed with the feed solution.