Browsing by Author "Ungerer, M.J."
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Comparison of extractants for the separation of TaF5 and NbF5 in different acidic media
Ungerer, M.J.; Van der Westhuizen, D.J.; Lachmann, G.; Krieg, H.M. (Elsevier, 2014)To optimise the solvent extraction (SX) of Ta and Nb, eight different extractants were investigated, including the cation exchangers di-iso-octyl-phosphinic acid (PA) and di-(2-ethylhexyl)-phosphoric acid (D2EHPA), the ... -
DFT modelling of tantalum pentafluoride extraction with phosphorus-based extractants – a molecular dynamics study
Ungerer, M.J.; Van Sittert, C.G.C.E.; Van der Westhuizen, D.J.; Krieg, H.M. (Elsevier, 2019)Solvent extraction (SX) is a powerful method for both the separation and extraction of metals, resulting in high purity metals. The transition metals tantalum (Ta) and niobium (Nb) are of considerable significance, for ... -
Molecular modelling of species pertaining to the solvent extraction of tantalum penta-fluorides
Ungerer, M.J. (North-West University, 2018)Solvent extraction (SX) is used for the separation and purification of various metals, including tantalum (Ta) and niobium (Nb). Industrial processes for the separation of Ta and Nb traditionally use high concentrations ... -
Molecular modelling of tantalum fluoride in sulphuric acid medium: a DFT study
Ungerer, M.J.; Van der Westhuizen, D.J.; Krieg, H.M.; Van Sittert, C.G.C.E. (Elsevier, 2019)During the solvent extraction (SX) experiments of tantalum (Ta) and niobium (Nb), the aqueous phase consisted of tantalum- and niobium penta-fluoride (Ta(Nb)F5), water (H2O) and sulphuric acid (H2SO4), which was contacted ... -
Molecular modelling of tantalum in an aqueous phase
Ungerer, M.J.; Van Sittert, C.G.C.E.; Van der Westhuizen, D.J.; Krieg, H.M. (SAIMM, 2017)The transition metals tantalum (Ta) and niobium (Nb) are of significant importance, for example in the nuclear energy sector where they are used as cladding materials, as well as in capacitors and specialized materials. For ... -
Molecular modelling of tantalum penta-halides during hydrolysis and oxidation reactions
Ungerer, M.J.; Van Sittert, C.G.C.E.; Van der Westhuizen, D.J.; Krieg, H.M. (Elsevier, 2016)The transition metals tantalum (Ta) and niobium (Nb), which are usually found together in nature, have similar chemical and physical properties, making their separation challenging. There are various methods available for ... -
Sulphur dioxide oxidation mechanism on Pt surfaces : a DFT study
Nel, Theunis (North-West University (South Africa), 2021)Lately, significant interest has risen towards the development of renewable energy in order to lower fossil fuel consumption and its environmental impact. Hydrogen (H2) has been proposed as a viable alternative to fossil ...