中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 26 No. 6 June 2016 |
(1. School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China;
2. Engineering Research Center for Cold and Arid Regions Water Resource Comprehensive Utilization,
Ministry of Education, Lanzhou Jiaotong University, Lanzhou 730070, China)
Abstract:The process parameters were optimized for the electrodeposition of cobalt from cobalt chloride solution in the membrane electrolytic reactor. Effects of parameters such as catholyte composition, current density and temperature on the current efficiency, specific power consumption and quality of deposition were studied. The catholyte was a mixed solution of cobalt chloride, the initial middle electrolyte consisted of diluted hydrochloric acid, and the anolyte was sulfuric acid. An anion exchange membrane separated the catholyte from the middle electrolyte, and a cation exchange membrane separated the anolyte from the middle electrolyte. The results showed that a maximum current efficiency of 97.5% was attained under the optimum experimental condition of an catholyte composition of 80 g/L Co2+, 20 g/L H3BO3, 3 g/L NaF and pH of 4, at a cathode current density of 250 A/m2 and a temperature of 50 °C. HCl could be produced in the middle compartment electrochemically up to 0.45 mol/L.
Key words: cobalt; electrodeposition; anion exchange membrane; cation exchange membrane; membrane electrolytic reactor