Title: Homogeneous liquid–liquid extraction of neodymium(III) by choline hexafluoroacetylacetonate in the ionic liquid choline bis(trifluoromethylsulfonyl)imide
Authors: Onghena, Bieke
Jacobs, Jeroen
Van Meervelt, Luc
Binnemans, Koen # ×
Issue Date: 2014
Publisher: Royal Society of Chemistry
Series Title: Dalton Transactions vol:43 issue:30 pages:11566-11578
Abstract: The ionic liquid choline bis(trifluoromethylsulfonyl)imide, [Chol][Tf2N], was used for the extraction of neodymium(III), in combination with choline hexafluoroacetylacetonate, [Chol][hfac], as the extractant. The binary mixture of [Chol][Tf2N] and water shows temperature-dependent phase behavior, with an upper critical solution temperature of 72 °C. A novel extraction technique, homogeneous liquid–liquid extraction (HLLE), was applied to this solvent system. HLLE is based on the use of thermomorphic solvent mixtures and has the advantage of forming a homogeneous phase during mixing. Extraction is not kinetically hindered by an interface and the extraction equilibrium is reached faster than in the case of heterogeneous mixing in conventional solvent extraction. Several extraction parameters were studied for the extraction of neodymium(III) with [Chol][hfac]: temperature, pH, extractant concentration and loading of the ionic liquid phase. A speciation study was performed to determine the stoichiometry of the extracted neodymium(III) complex and a plausible extraction mechanism is proposed. Neodymium is extracted as a tetrakis hexafluoroacetylacetonate complex with one choline cation as counter ion. The crystal structure of the extracted complex showed the presence of a coordination bond between the choline counter ion and the neodymium(III) center, resulting in a coordination number of nine. The stripping of the loaded neodymium and the influence of acid and extractant concentrations on the phase behavior of the [Chol][Tf2N]–H2O system were investigated.
ISSN: 1477-9226
Publication status: published
KU Leuven publication type: IT
Appears in Collections:Molecular Design and Synthesis
Biochemistry, Molecular and Structural Biology Section
× corresponding author
# (joint) last author

Files in This Item:
File Description Status SizeFormat
315cholineHLLE.pdfMain article Published 770KbAdobe PDFView/Open Request a copy
Postprint_Manuscript_CholTf2N.pdf Published 967KbAdobe PDFView/Open

These files are only available to some KU Leuven Association staff members


All items in Lirias are protected by copyright, with all rights reserved.

© Web of science