K. K. Sahu

Publications (2)1.81 Total impact

• Article: Mixed solvent systems for the extraction and stripping of iron(III) from concentrated acid chloride solutions

  K. K. Sahu, R. P. Das
  [show abstract] [hide abstract]
  ABSTRACT: The extraction of concentrated iron(III) from acid chloride solutions has been investigated with methyl isobutyl ketone (MIBK), tri-n-butyl phosphate (TBP), di(2-ethylhexyl) phosphoric acid (D2EHPA), and their mixtures in various proportions, at different acid concentrations. On comparing the extraction of iron(III) with mixed and individual extractant, it was found that both D2EHPA-MIBK and D2EHPA-TBP mixtures exhibit synergism, the latter having better extraction ability. The synergistic coefficients, at different initial acid concentrations for each mixed extractant system, were evaluated and compared. An increase in the concentration of MIBK and TBP in the mixed organic resulted in higher synergistic coefficient. The stripping of iron(III) from loaded D2EHPA was found to increase with the strip feed acid concentration, while from loaded organic mixtures, it initially increased and then decreased. Stripping of iron(III) from D2EHPA-MIBK loaded solvent is better then D2EHPA-TBP. The extracted iron species formed and the stripping reactions have been proposed. Ultraviolet visible spectra of the stripped organic phase support the result and the proposed mechanisms.
  Metallurgical and Materials Transactions B 11/2000; 31(6):1169-1174. · 0.90 Impact Factor
• Article: Synergistic extraction of iron(III) at higher concentrations in D2EHPA-TBP mixed solvent systems

  K. K. Sahu, R. P. Das
  [show abstract] [hide abstract]
  ABSTRACT: The extraction of iron(III) from chloride solutions at macrolevel concentration by different solvents such as tri-n-butyl phosphate (TBP), di(2-ethylhexyl) phosphoric acid (D2EHPA), and their mixture in various proportions has been investigated at different acid concentrations. The synergistic extraction of iron(III) with a mixture of TBP and D2EHPA was studied and the results were compared with that of the extraction by individual solvent alone. An increase in the concentration of the synergist, TBP, in the D2EHPA-TBP solvent system resulted in an increase in the synergistic co-efficient value. The experimental data are treated graphically to explain the formation of organic phase extracted species, and the equilibrium extraction constants for the species are determined. It is found that a maximum of two molecules of TBP are adducted to the extracted species of the corresponding nonsynergistic system. Stripping of iron(III) with hydrochloric acid from loaded D2EHPA was found to increase with an increase in acid concentration. In the case of D2EHPA-TBP mixtures, stripping efficiency was increased with an increase in acid concentration up to a certain level and then it was decreased. The experimental results indicate that an iron exchange reaction between loaded D2EHPA and TBP proceeds during stripping at a higher concentration of hydrochloric acid (from mixed loaded solvent system). A plausible mechanism for iron(III) extraction and stripping has been discussed.
  Metallurgical and Materials Transactions B 03/1997; 28(2):181-189. · 0.90 Impact Factor