METHOD FOR RECOVERING RHODIUM FROM HARDLY REDUCIBLE RHODIUM COMPLEX ION

• Main Authors: ASANO SATOSHI, TAKAHASHI NOBUO
• Format: Patent
• Language: English
• Published: 21.06.1994
• Edition: 5
• Subjects: APPARATUS THEREFOR; CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION ORPROCESSING OF GOODS; COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSESC01D OR C01F; ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; FERROUS OR NON-FERROUS ALLOYS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; INORGANIC CHEMISTRY; METALLURGY; PRETREATMENT OF RAW MATERIALS; PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY ORREFINING OF METALS; 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

PURPOSE:To selectively recover metallic rhodium from a soln. of a hardly reducible rhodium complex in a high yield. CONSTITUTION:Nitric acid as an oxidizing agent is added to an aq. soln. contg. hardly reducible rhodium complex ions and >=3mol/l, preferably >=6mol/l chloride ions allowed to coexist with the complex ions so as to attain >=0.8 V, preferably >=1.0V standard oxidation-reduction potential and they are brought into a reaction while keeping the soln. at 50 deg.C to the b.p. The standard oxidation-reduction potential of the resulting aq. soln. is then maintained in the range of 0.3-0.5V and a reducing agent is added to selectively deposit rhodium. Rhodium is recovered from hardly reducible rhodium complex ions.