US EPA

2037574 

Journal Article 

Selective precipitation of mixed nickel-cobalt hydroxide 

Harvey, R; Hannah, R; Vaughan, J 

2011 

Yes 

Hydrometallurgy
ISSN: 0304-386X 

105 

3-4 

222-228 

10.1016/j.hydromet.2010.10.003 

WOS:000286719500005 

The precipitation parameters of mixed hydroxide precipitate (MHP) using caustic calcined magnesia were evaluated at simulated industrial conditions using a mixed sulphate-chloride feed solution and fine magnesia powder. Controlling the rate of magnesia addition was found to decrease the manganese content of the precipitate but the benefit was minimal. Thermodynamic analysis combined with oxidation-reduction potential measurements suggests that some of the manganese is reporting to the solids by an oxidative precipitation reaction. The oxidative precipitation of manganese in air was confirmed experimentally. Contacting MHP with feed solution was found to substantially improve the solids' nickel and cobalt grade while decreasing the manganese and magnesium content. Precipitate contacting with the feed solution also resulted in a higher concentration of sulphate and chloride in the precipitate. (C) 2010 Elsevier B.V. All rights reserved. 

Nickel-cobalt hydroxide; Magnesia; Precipitation; Thermodynamics; Manganese