RECOVERING METHOD FOR INDIUM FROM INDIUMMCONTAINING SUBSTANCE

摘要

PURPOSE:To efficiently recover In from an In-contg. substance in a high yield by subjecting a slon. leached from the substance with sulfuric acid to reduction and neutralization; separating a precipitate formed; alkali-treating it in the presence of hydrogen peroxide; sulfide-treating a soln. leached from the resulting slurry with sulfuric acid; and neutralizing the sulfurized soln. CONSTITUTION:A soln. leached from an In-contg. substance such as lead slag contg. coexistent As, Pb, Zn, etc. with sulfuric acid is neutralized to pH3-4 with alkali in the presence of a reducing agent, and a precipitate formed is separation- recovered. By alkali treatment in the presence of hydrogen peroxide the precipitate is adjusted to pH=13 and filtered. A soln. leached from the resulting slurry with sulfuric acid is sulfurized with sulfide such as sodium sulfide, and a precipitate formed is removed to obtain a sulfurized soln., which is then neutralized to pH3-4 with alkali to form a precipitate. This precipitate is collected, and by further purifying the resulting slurry, In is recovered.