1999 年 115 巻 3 号 p. 185-188
Room temperature leaching of ITO (Indium Tin Oxide) scrap has been carried out to extract mainly indium, using H2SO4 solution of 1N, after mechanochemically treated with Al2O3 powder by means of a planetary mill. The crystallinity of In2O3 in the scrap was changed into amorphous state by the mechanochemical treatment, although In2O3 maintained the crystal structure partially even in the prolonged treatment. The degradation of crystallinity of In2O3 in the scrap resulted in easy extraction of indium at high yield in the leaching process. Al2O3 powder in the scrap plays a significant role to make In2O3 amorphous.