钴酸锂废极片中钴回收新工艺研究

Study on the new process for the recovery of cobalt from spent lithium cobalt oxide

研究了钴酸锂废极片中回收钴的新工艺,采用硫酸+双氧水体系对钴酸锂废极片进行浸出,其中:H2SO42.0mol/L、H2O21.2mL/g、温度80℃、浸出时间120min,钴的浸出率达到99%,而铝的溶解则控制在35.1%。浸出液加入碳酸氢铵调pH值至5.5除铝,然后加入草酸铵沉钴,所得草酸钴煅烧成氧化钴,所得产品可达到Co2O3-Y1(GB6518-86)的要求,钴的回收率为97%。

A new technique process for spent lithium cobalt oxide reclamation was developed. Spent lithium cobalt oxide was leached by sulphuric acid and hydrogen peroxide, and the optimum performance conditions of the leaching were established. At the concentration of sulphuric acid of 2.0 mol/L, the dosage of hydrogen peroxide of 1.2 mL/g, the temperature of 80 ℃ and the leaching time of 120 min, the leaching rate of cobalt would reach 99% under the optimum conditions while that of aluminum could be controlled to 35.1%. Aluminum could be removed thoroughly while the pH of leaching solution was adjusted to 5.5 by adding ammonium bicarbonate. Then the cobalt was precipitated with ammonium oxalate. The obtained product cobalt oxide by calcinations met the requirements of Co203-Y 1 （GB 6518-86）, and a cobalt recovery of 97% was obtained.