Separation of cobalt and nickel from sulfate media using P507-N235 system

ABSTRACT

Separation of cobalt and nickel from sulfate media was investigated, using a extraction system of 30% 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (P507)+15% trioctyl/decylamine (N235)+55% sulfonated kerosene. About 41 wt% Co²⁺ was extracted with 1.6 wt% co-extraction of Ni²⁺ at O/A ratio of 2:1. Scrubbing of Ni²⁺ and stripping of Co²⁺ could be achieved from the loaded organic phase, using water and 0.05 mol/L H₂SO₄, respectively. Cobalt extraction percentage decreased with increasing Mg²⁺ concentration, but this influence was negligible as [Mg²⁺] < 0.1g/L. The favorable equilibrium pH was 4–4.8. A different E-pH curve was observed in the P507-N235 system compared to the saponified P507 system.

KEYWORDS:

• Cobalt
• extraction
• nickel
• magnesium
• P507-N235 system

Funding

This work is financially supported by National Natural Science Foundation of China (No. 51264003), Guangxi Natural Science Foundation (No. 2014GXNSFAA118325) in China and Guangxi Key Research and Development Plan (No. AB17129011) in China.

Additional information

Funding

This work is financially supported by National Natural Science Foundation of China (No. 51264003), Guangxi Natural Science Foundation (No. 2014GXNSFAA118325) in China and Guangxi Key Research and Development Plan (No. AB17129011) in China.