METHOD FOR PRODUCING NICKEL-CONTAINING ACIDIC SOLUTION

• Main Authors: ASANO, SATOSHI, TAKANO, MASATOSHI, KIKUTA, NAOKO
• Format: Patent
• Language: English; French; German
• Published: 13.04.2016
• Subjects: BASIC ELECTRIC ELEMENTS; CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION ORPROCESSING OF GOODS; CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATERTREATMENT OR WASTE MANAGEMENT; ELECTRICITY; 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; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY; 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

The present invention provides a production method for obtaining a solution with a high content of nickel and cobalt by more simply and more efficiently separating nickel and cobalt from a positive electrode material of a spent nickel-metal hydride battery, a production waste material of a positive electrode material, or the like. The method is characterized in that an acid solution containing nickel is obtained by treating a positive electrode material of a nickel-metal hydride battery through the steps of: a water-washing step, wherein a positive electrode material of a nickel-metal hydride battery is water-washed by adding water, and then separated to form a positive electrode material after water-washing and a water-washed slurry; an acid-washing step, wherein an acid is added and mixed into the positive electrode material after water-washing which has been obtained in the water-washing step, and, with pH maintained in a range of not less than 0.0 and not more than 3.5, separation is performed to form a positive electrode material after acid-washing and an acid-washed slurry; and a dissolution step, wherein the positive electrode material after acid-washing which has been obtained in the acid-washing step is separated into a nickel solution and a dissolution residue by adding both an acid and an oxidizing agent, or any one of an acid and an oxidizing agent.