RECOVERING METHOD FOR INDIUM FROM WASTE PLATING LIQUID CONTAINING CYANIDE AND INDIUM

摘要

PURPOSE:To recover high purity In in a high yield by treating the titled bath with a Cl type anion exchange resin, washing the resin with formalin or the like, carrying out elution with nitric acid, and adding an NH3 soln. to the eluate to precipitate In as indium hydroxide, which is then separated. CONSTITUTION:The titled bath is treated with a Cl type anion exchange resin to allow In and Zn to be adsorbed as the cyano-complex, and the resin is washed with formalin or chloral hydrate to libertate In3+ and Zn2+. These cations are then eluted with dil. nitric acid, and by adding an NH3 soln. to the elutate, In alone is precipiated as indium hydroxide. This precipitate is separated and dried to recover pure indium hydroxide in a high yield.