RECOVERY METHOD OF BISMUTH

• Main Authors: IKUTA DAIGO, OKADA SATOSHI
• Format: Patent
• Language: English
• Published: 15.08.2013
• Subjects: CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION ORPROCESSING OF GOODS; FERROUS OR NON-FERROUS ALLOYS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; METALLURGY; PRETREATMENT OF RAW MATERIALS; PRODUCTION AND REFINING OF METALS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; TREATMENT OF ALLOYS OR NON-FERROUS METALS; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE

PROBLEM TO BE SOLVED: To provide a recovery method of bismuth, capable of efficiently separating bismuth from an acidic solution produced in copper refining and recovering high-purity bismuth.SOLUTION: The recovery method of bismuth includes: subjecting an acidic solution containing bismuth to precipitate a bismuth salt, and reducing a solution of the precipitate to separate and recover bismuth from coexisting metals. The neutralization treatment is performed in two stages at ordinary temperature. In the first neutralization treatment, the pH of the bismuth-containing solution is adjusted to 0.5-1.5 over a period of 60 minutes or more to form a precipitate of coexisting metals to be precipitated in the pH region, and the precipitate is filtered. In the second neutralization treatment, the pH of the resulting filtrate is adjusted to 2-3 to form a precipitate containing bismuth, the bismuth-containing precipitate is recovered and dissolved in hydrochloric acid, and the solution is iron-reduced to recover precipitated metal bismuth.