Korean Journal of Chemical Engineering, Vol.30, No.1, 194-200, 2013
Separation of Co(II) and Ni(II) from thiocyanate media by hollow fiber supported liquid membrane containing Alamine300 as carrier - investigation on polarity of diluent and membrane stability
The separation of cobalt(II) and nickel(II) ions by HFSLM has been presented. The feed solution is 0.5M thiocyanate containing 300 ppm each of cobalt(II) and nickel(II) ions, whereas extractant is Alamine300 and the stripping solution is ammonia. Cobalt(II) is more preferable with Alamine300 than nickel(II). The effects of pH, Alamine300 concentration and ammonia concentration were investigated. Seven diluents were used: hexane, decanol, chlorobenzene,
benzene, dichloromethane, ethylene dichloride and chloroform with different polarity indexes, from 0.1-4.1. Nickel(II) ion which is unpreferable with Alamine300 was used as a tracer to determine the membrane stability. The polarity of the diluents was found to be the main factor influencing the extraction performance and stability of a liquid membrane. The decreasing of polarity of the diluent can prolong the membrane stability, but the percentages of extraction and stripping decreased. The longest lifetime, 200 minutes, was obtained by using hexane as a diluent with the polarity index of 0.1.
Membrana - Charlotte the Liqui-Cel Team, 2011, Properties of the hollow fiber module, Retrieved February 20, 2011, From Polypore International Inc., Web site: http://www.liqui-cel.com.