Synergistische Extraktion von Lanthaniden mit Thenoyltrifluoraceton und Trioctylamin

Synergic Effect of Tribenzylamine on the Extraction of Fe (III) with 2-Thenoyltrifluoroacetone in Chloroform

“…This indicates the presence of one amine molecule in the amine adduct. The slope analyses results support the general formula of the extracted adduct Fe(TTA) 3 TBA under the experimental conditions employed. The reaction involving the formation of the synergic species may be written as [18].…”

“…The rate determining step in the Fe (III) /TTA /TBA system is the usual keto-enol equilibrium and the synergic reaction may be due to the enhanced solubility of the amine adduct of TTA-metal chelate. The spectral evidence supports the postulation that there is a weak bond formation between the nitrogen atom of TBA and the central metal ion in the Fe(TTA) 3 TBA. This is supported by the work of NEWMAN [2] and Li [15].…”

“…The reaction of the metal ion with an enolate ion is the rate determining step [14]. Synergic reaction is likely to proceed through the following steps: The identical absorption spectra of Fe(TTA) 3 and Fe(TTA) 3 TBA (Fig. 2) indicates that metal ligand interaction is similar in both cases.…”

“…a) Distribution of ΗΤΤΑ into the aqueous phase b) Ionization of ΗΤΤΑ followed by the reaction of Fe (III) with TTA enolate ion and c) Chloroform may form a solvate with Fe(TTA) 3 through hydrogen bonding.…”

“…It was, therefore, anticipated that the addition of a synergic reagent such as tribenzylamine (TBA) in this system might promote the rate of extraction of iron. The synergic effect of amines on the extraction of chelates of ΗΤΤΑ has been reported for many metal ions under a variety of conditions [1][2][3]. GENOV and DUKOV [4] studied the extraction of praseodymium with ΗΤΤΑ in the presence of trioctylamine (TOA) in various solvents including chloroform from mineral acid solutions.…”