Thermodynamics of extraction of MoO42- from aqueous sulfuric acid media with TBP dissolved in kerosene

Molybdenum distribution between TBP dissolved in kerosene and aqueous sulfuric acid media is investigated, The influential parameters are temperature, molarity of sulfuric acid and concentration of TBP. The results show that the extraction reaction is exothermic. Increasing the TBP concentration at sulfuric acid molarities greater than 4 M does not change the distribution factor of molybdenum. The distribution factor of molybdenum in sulfuric acid media with TBP has a maximum at 0.03 mol/l of H2SO4 and a minimum near 0.2 mol/l of H2SO4, The stoichiometric reaction indicates neutralization of 2 mol of H+ with 1 mol of MoO42- and solvating a neutral molecule with 3 mol of TBP. At the lower acidity, the complex structure may be 3TBP H2Mo2O5(SO4)(2). (C) 2000 Elsevier Science B.V. All rights reserved.