Supercritical CO2 extraction of molybdenum-ligand complexes from sulfuric solutions
The development of environmental-friendly process for strategic metal extraction, limiting organic solvent use and effluent production, appears to be quite a challenging purpose. Production of pure molybdenum using supercritical CO2 extraction process, from sulfuric solution obtained by ore or used catalyst leaching, has been evaluated. Two organic ligands, trioctylamine and 2-ethylhexyl 2-ethylhexylphosphonic acid, were studied to extract Mo as metal complexes solubilized in supercritical CO2. Extraction with trioctylamine revealed to be non-efficient due to a lack of Mo-trioctylamine complex solubility in CO2, even if extraction selectivity of molybdenum versus iron impurity was interesting. On the contrary, extraction with 2-ethylhexyl 2-ethylhexylphosphonic acid leads to high Mo collection efficiency (up to 90% in 7 h). However, no selectivity was observed between molybdenum and zirconium. The selectivity of 2-ethylhexyl 2-ethylhexylphosphonic acid towards molybdenum in presence of iron was better but clearly decreased in presence of zirconium.
Laurence Hung, Audrey Hertz, Didier Hartmann, Frédéric Charton, Olivier Boutin. Supercritical CO2 extraction of molybdenum-ligand complexes from sulfuric solutions. Journal of Supercritical Fluids, Elsevier, 2016, 111, pp.97-103. ⟨10.1016/j.supflu.2016.01.017⟩. ⟨hal-01297659⟩
Journal: Journal of Supercritical Fluids
Date de publication: 01-05-2016