Loading...

Thermodynamics of vanadium (V) solvent extraction by mixture of D2EHPA and TBP

Cheraghi, A ; Sharif University of Technology | 2015

833 Viewed
  1. Type of Document: Article
  2. DOI: 10.1016/j.minpro.2015.03.011
  3. Publisher: Elsevier , 2015
  4. Abstract:
  5. In the present study, the thermodynamics and mechanisms of vanadium extraction by a mixture of bis-2-ethylhexyl phosphoric acid (D2EHPA) and tri-n butyl phosphate (TBP) from sulfate medium were investigated. It was found that the maximum extraction percent of vanadium occurs at pH 1.8 under ambient conditions; this phenomenon was ascribed to the predominant presence of cationic species of vanadium (VO2+) at this pH. Based on the Fourier Transform Infrared (FT-IR) spectrums, the POH bond of D2EHPA was found responsible for the extraction of VO2+ species through a cationic exchange mechanism. Employing the slope analysis method showed that the stoichiometric reaction between VO2+ and D2EHPA was VO2++RH→VO2R¯+H+ regardless of the D2EHPA concentration. It was also shown that the TBP has no synergistic effect on the VO2+ extraction except in the experiments conducted at 60 °C. This was further elucidated by applying a modifying factor for TBP in the slope analysis method. Results showed that vanadium extraction was an endothermic reaction with an apparent molar enthalpy of 22.76 kJ/mol
  6. Keywords:
  7. Extraction ; Mechanisms ; Mixtures ; Thermodynamics ; Vanadium ; D2EHPA ; Endothermic reactions ; Fourier transform infrared ; Stoichiometric reaction ; Synergistic effect ; TBP ; Tri-n-butyl phosphate ; Vanadium extractions ; Solvent extraction
  8. Source: International Journal of Mineral Processing ; Volume 138 , May , 2015 , Pages 49-54 ; 03017516 (ISSN)
  9. URL: http://www.sciencedirect.com/science/article/pii/S0301751615000630