METHOD FOR RECOVERING NOBLE METAL

摘要

PURPOSE:To facilitate the recovery of noble metal and the reutilization of a soln. contg. I and an I compound at the time of extracting the noble metal by the above soln. and reducing and recovering the noble metal by specifically regulating the pH in the molten extracted soln. of the noble metal. CONSTITUTION:Noble metal is extracted by melting from a recovered material contg. the noble metal by a soln. contg. I and an I compound. Alkali is then added to the molten extracted soln. of the noble metal to convert it into strong alkali of >=12pH; the noble metal is reduced to deposit and is separated to recover. The pH of the soln. after the recovery of the noble metal is then reduced into the soln. contg. I and an I compound to reuse the soln. By this method, the soln. of I and an I compound after the reduction and deposition of the noble metal is reutilized as the I and I compound-contg. soln. without executing it to harmless treatment.