Solvent extraction of molybdenum (VI) from diluted and concentrated hydrochloric acid
The solvent extraction of Mo (VI) from diluted and concentrated HCl solutions with tri-n-butyl phosphate (TBP) has been studied. The percentage Mo (VI) extraction (E%) reaches maximal levels of 49.60% and 51.20% at pH 1.0 and 4.0 respectively, however, it is much higher (E% = 85.60 –90.80%) in concentrated HCl (2.0 – 7.0M) solutions and decreases with temperature. The mechanism of extraction appears to be through the formation of condensed molybdic acid n(MoO3.2H2O). mTBP at low pH but involves molybdenyl species MoO2Cl2. (H2O) 2. mTBP in concentrated acid medium and pH 4-6. Electronic and infrared spectra data have been used to deduce the nature of the extracted species.
Keywords: Molybdenum (VI), extraction, TBP, molybdic acid.
Global Journal of Pure and Applied Sciences Vol. 14 (3) 2008: pp. 289-294