Selective Extraction and Complexation Studies for Thorium(IV) with Bis-triamide Extractants: Synthesis, Solvent Extraction, EXAFS, and DFT

Palladium (Pd) electroplating is widely practiced in the manufacture of advanced electronic devices. The Pd(II) present in spent electroplating solutions is treated by cementation with zinc (Zn) metal powder. In order to recover pure Pd from the cemented Pd, a process that consisted of leaching followed by solvent extraction was investigated. For this purpose, solvent extraction experiments using synthesized ionic liquids (ILs) with organic and inorganic anions were performed to find separation conditions at which selective extraction of Pd(II) over Zn(II) from synthetic H2SO4 leaching solutions is possible. The concentration of sulfuric acid was varied from 0.5 to 9 M. The complete separation of Pd(II) over Zn(II) by ILs such as ALi–CY301 (N-methyl-N,N,N-trioctylammonium bis(2,4,4-trimethylpentyl) dithiophosphinic), ALi–SCN (N-methyl-N,N,N-trioctylammonium thiocyanate), ALi–I (N-methyl-N,N,N-trioctylammonium iodide) and ALi–Br (N-methyl-N,N,N-trioctylammonium bromide) depends on H2SO4 concentration, while ALi–LIX63 (N-methyl-N,N,N-trioctylammonium 5,8-diethyl-7-hydroxydodecane-6-oxime) and ALi–LIX84 (N-methyl-N,N,N-trioctylammonium 2-hydroxy-5-nonylacetophenone oxime) can completely separate Pd(II) irrespective of H2SO4 concentration. Additionally, the mixture of HCl and thiourea, aqua regia solution, NH3 solution and the mixture of NH4Cl and NH3 are powerful stripping agents for Pd(II) from the loaded ALi–LIX63/ALi–LIX84, ALi–CY301, ALi–Br/ALi–I and ALi–SCN, respectively. However, application of the separation conditions to the real 5 M sulfuric acid leaching solutions of cemented Pd indicated that it was difficult to separate the two ions by extraction with ALi–LIX63 and ALi–LIX84. Use of NaClO as an oxidizing agent during the sulfuric acid leaching of real cemented Pd resulted in an enhancement of Zn(II) extraction by ALi–LIX63 and ALi–LIX84. Therefore, removal of chloride ions from the sulfuric acid leaching solutions is necessary to apply the separation conditions obtained from synthetic sulfuric acid leaching solutions.

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The use of selective extraction chromatographic columns as an alternative to solvent extraction for the separation of uranium followed by the use of Arsenazo III as a calorimetric reagent for uranium determination

10.2172/10183134 ◽

1994 ◽

Cited By ~ 1

Author(s):

C.J. Miller ◽

J.R. Del Mastro

Keyword(s):

Solvent Extraction ◽

Selective Extraction ◽

Arsenazo Iii ◽

Chromatographic Columns ◽

Uranium Determination

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Selective extraction of triazine herbicides based on a combination of membrane assisted solvent extraction and molecularly imprinted solid phase extraction

Journal of Chromatography A ◽

10.1016/j.chroma.2010.12.019 ◽

2011 ◽

Vol 1218 (5) ◽

pp. 647-653 ◽

Cited By ~ 39

Author(s):

Luke Chimuka ◽

Manuela van Pinxteren ◽

Johan Billing ◽

Ecevit Yilmaz ◽

Jan Åke Jönsson

Keyword(s):

Solvent Extraction ◽

Solid Phase Extraction ◽

Solid Phase ◽

Selective Extraction ◽

Phase Extraction ◽

Triazine Herbicides ◽

Molecularly Imprinted

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Studies of Selective Removal of Iron (III) from the Simulated Bauxite Hydrochloric Acid Leaching Liquor by Solvent Extraction

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.746.31 ◽

2013 ◽

Vol 746 ◽

pp. 31-34

Author(s):

Xing Yao Wang ◽

Ma Cong ◽

Juan Liu

Keyword(s):

Solvent Extraction ◽

Hydrochloric Acid ◽

Acid Leaching ◽

Selective Extraction ◽

Selective Removal ◽

Extraction Technique ◽

Factors Influencing ◽

Hydrochloric Acid Leaching ◽

Solvent Extraction Technique ◽

Maximum Removal

Solvent extraction technique was performed to optimize the conditions for maximum removal of iron (III) from the simulated bauxite hydrochloric acid leaching liquor of FeCl3+AlCl3+CaCl2+HCl. Some factors influencing the extraction, such as the extractant and concentration of Fe, Al, and Ca were investigated. The results indicated that the N235 is an effective extractant for selective extraction of iron (III) from chloride liquor. The concentration of Fe in raffinate is under 0.0165 gL-1 and the losing of Al is 0.50 % by N235.

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Selective Solvent Extraction of Silver(I) by Tris-Pyridyl Tripodal Ligands and X-Ray Structure of a Silver(I) Coordination Polymer Incorporating One Such Ligand

Australian Journal of Chemistry ◽

10.1071/ch14540 ◽

2015 ◽

Vol 68 (4) ◽

pp. 549 ◽

Cited By ~ 4

Author(s):

David. J. Bray ◽

Jack K. Clegg ◽

Marco Wenzel ◽

Kerstin Gloe ◽

John C. McMurtrie ◽

...

Keyword(s):

Solvent Extraction ◽

Coordination Polymer ◽

Metal Ion ◽

Silver Ions ◽

Selective Extraction ◽

Metal Extraction ◽

Tripodal Ligands ◽

X Ray ◽

Selective Solvent Extraction ◽

Pyridyl Ligand

Two tripodal ligands, each derived from 1,1,1-tris(hydroxymethyl)ethane and terminated respectively by 4-pyridyl (L1) and 2-pyridyl groups (L2), have been synthesised. Competitive seven-metal extraction studies (H2O/CHCl3) incorporating equal concentrations of cobalt(ii), nickel(ii), copper(ii), zinc(ii), silver(i), cadmium(ii), and lead(ii) in the aqueous phase and L1 or L2 in the organic phase showed selective extraction of silver(i) in each case. A parallel solvent extraction experiment involving a related tripodal tris-pyridyl ligand (L3) based on a 1,3,5-substituted aryl ring scaffold and incorporating thioether sulfurs in each tripod arm also showed extraction selectivity for silver(i); extraction efficiencies towards this metal ion fall in the order L3 > L1 > L2. Physical data are in accord with L1 forming a capsule-like complex of type [Ag3L12]3+ in which silver ions link pairs of pyridyl groups from different ligands. In contrast, L2 yields a complex of type [Ag2L2(NO)3]n whose X-ray structure showed it to be a two-dimensional coordination polymer in which the three pyridyl donors of each L2 coordinate to three silver(i) centres, two of which are crystallographically distinct, with the centres also bonded to bidentate and/or bridging bidentate nitrato groups.

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