Extraction Equilibrium of Ni(II) in the Ni<sup>2+</sup>-SO<sub>4</sub><sup>2-</sup>-Ac<sup>-</sup>(Na<sup>+</sup>, H<sup>+</sup>) - Cyanex 272 (H<sub>2</sub>A<sub>2</sub>)-kerosene-3%(v/v) Octan-1-ol System
Keywords:Extraction equilibrium, Ni(II) extraction, Cyanex 272, Sulphate-acetato medium
The title system has been studied elaborately. 3% (v/v) octan-1-ol is added as de-emulsifier. Equilibration time is < 2 min. Distribution ratio (D) at constant pH(eq) and [H2A2] is independent of [Ni(II)](aq). The pH dependency is always found to be 2; whilst the extractant dependence is found to vary from 1 (at lower concentration region, lcr) to 3 (at high concentration region, hcr). Moreover, the distribution ratio is found to be inversely proportional to (1+6.92 [SO42-]) and [Ac-]. Based on these results, the extraction equilibrium reactions have been proposed at various parametric conditions. The extraction process is endothermic (?H = 54.66 kJ/mol). The Kex values at 303 K are evaluated to be 10-11.086 and 10-11.56 at lcr and hcr of extractant, respectively. The maximum loading capacity is 21.28 g Ni(II) per 100 g extractant indicating the formation of NiAcA at maximum loading. The stripping ability of various inorganic acids towards loaded nickel, as well as, the possibilities of separation of Ni(II) from its binary mixtures with other ions of 3d-block elements have also been investigated.
Keywords: Extraction equilibrium; Ni(II) extraction; Cyanex 272; Sulphate-acetato medium; Kerosene-octanol.
© 2012 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.
J. Sci. Res. 4 (1), 83-97 (2012)
How to Cite
© Journal of Scientific Research
Articles published in the "Journal of Scientific Research" are Open Access articles under a Creative Commons Attribution-ShareAlike 4.0 International license (CC BY-SA 4.0). This license permits use, distribution and reproduction in any medium, provided the original work is properly cited and initial publication in this journal. In addition to that, users must provide a link to the license, indicate if changes are made and distribute using the same license as original if the original content has been remixed, transformed or built upon.