skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Water-soluble Schiff base-actinyl complexes and their effect on the solvent extraction of f-elements

Journal Article · · Dalton Transactions
DOI:https://doi.org/10.1039/C6DT01357K· OSTI ID:1418758
 [1];  [2]; ORCiD logo [3];  [3];  [1]
  1. Univ. of California, Irvine, CA (United States). Dept. of Chemical Engineering and Materials Science
  2. Univ. of California, Irvine, CA (United States). Dept. of Chemical Engineering and Materials Science; Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
+ Show Author Affiliations

Conventional solvent extraction of selected f-element cations by bis(2-ethylhexyl)phosphoric acid (HDEHP) yields increased extraction from aqueous to organic solution along the series Np(V) < Cm(III) < Eu(III) < U(VI), with distribution ratios all within two orders of magnitude. However, in the presence of the water-soluble tetradentate Schiff base (N,N'-bis(5-sulfonatosalicylidene)-ethylenediamine or H2salenSO3), selective complexation of the two actinyl cations (Np(V) and U(VI)) resulted in an extraction order of Np(V) < U(VI) << Eu(III) < Cm(III). The extraction of neither Cm(III) or Eu(III) by HDEHP are significantly impacted by the presence of the aqueous phase Schiff base. Despite observed hydrolytic decomposition of H2salenSO3 in aqueous solutions, the calculated high conditional stability constant (β11 = 26) for the complex [UO2(salenSO3)]2- demonstrates its capacity for aqueous hold-back of U(VI). UV-visible-NIR spectroscopy of solutions prepared with a Np(VI) stock and H2salenSO3 suggest that reduction of Np(VI) to Np(V) by the ligand was rapid, resulting in a pentavalent Np complex that was substantially retained in the aqueous phase. Lastly, results from 1H NMR of aqueous solutions of H2salenSO3 with U(VI) and La(III), Eu(III), and Lu(III) provides additional evidence that the ligand readily chelates U(VI), but has only weak interactions with trivalent lanthanide ions.

Research Organization:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Organization:
USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE National Nuclear Security Administration (NNSA)
Grant/Contract Number:
AC52-06NA25396; 12-LF-237294
OSTI ID:
1418758
Report Number(s):
LA-UR-16-23332; ICHBD9
Journal Information:
Dalton Transactions, Vol. 45, Issue 39; ISSN 1477-9226
Publisher:
Royal Society of ChemistryCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 7 works
Citation information provided by
Web of Science

References (29)

Preferential extraction of lanthanides over trivalent actinides by monoacidic organophosphates from carboxylic acids and from mixtures of carboxylic and aminopolyacetic acids journal January 1968
Synthesis and characterization of 2-quinoxalinol Schiff-base metal complexes journal April 2009
Challenging conventional f-element separation chemistry – reversing uranyl( vi )/lanthanide( iii ) solvent extraction selectivity journal January 2014
Water Suppression That Works. Excitation Sculpting Using Arbitrary Wave-Forms and Pulsed-Field Gradients journal February 1995
Separation of actinides and lanthanides: crystal and molecular structures of N,N′-bis(3,5-di-t-butylsalicylidene)-4,5-dimethyl-1,2-phenylenediamine and its uranium complex journal September 2004
Molecular Structure and Electrochemical Behavior of Uranyl(VI) Complex with Pentadentate Schiff Base Ligand: Prevention of Uranyl(V) Cation−Cation Interaction by Fully Chelating Equatorial Coordination Sites journal March 2010
The Chemistry of TALSPEAK: A Review of the Science journal December 2014
A tetrameric neptunyl(v) cluster supported by a Schiff base ligand journal January 2012
Talanta review1 journal March 1966
Purification of di-(2-ethylhexyl)phosphoric acid by precipitation of copper(II) di-(2-ethylhexyl)phosphate journal August 1969
Nuclear Magnetic Resonance as a Tool for Determining Protonation Constants of Natural Polyprotic Bases in Solution journal November 1995
Unexpected Actinyl Cation-Directed Structural Variation in Neptunyl(VI) A-Type Tri-lacunary Heteropolyoxotungstate Complexes journal April 2015
Some water-soluble Schiff-base complexes of nickel(II): the role of water journal January 1985
Extraction of uranium(VI) with binary mixtures of a quadridentate Schiff base and various neutral donors journal January 1998
Distribution of Neptunium between Di-(2-ethyl hexyl)-phosphoric Acid and Mineral Acids journal March 1961
New Insight into the Mechanism of the Conjugate Addition of Benzenethiol to Cyclic and Acyclic Enones and of the Corresponding Uranyl−Salophen-Catalysed Version journal February 2003
Spectrophotometry of Neptunium in Perchloric Acid Solutions 1 journal April 1951
Some Physicochemical Properties of (D2EHPA). 1. Distribution, Dimerization, and Acid Dissociation Constants of D2EHPA in a Kerosene/0.10 kmol m - 3 (Na + ,H + )Cl - System and the Extraction of Mn(II) journal January 2000
Determination of fructose 1,6-bisphosphate using a double-receptor sandwich type fluorescence sensing method based on uranyl–salophen complexes journal June 2013
Separation of neptunium, plutonium, americium and curium from uranium with di-(2-ethylhexyl)-phosphoric acid (HDEHP) for radiometric and ICP-MS analysis journal September 1998
X-ray Absorption Fine Structures of Uranyl(V) Complexes in a Nonaqueous Solution journal October 2009
Separations Chemistry for Actinide Elements: Recent Developments and Historical Perspective journal January 1997
Complexation of Pentavalent and Hexavalent Actinides by Fluoride journal January 1984
Cation-Cation Complexes of Pentavalent Uranyl: From Disproportionation Intermediates to Stable Clusters journal November 2010
Studies on singlet oxygen in aqueous solution. Part 2. Water-soluble square-planar nickel complexes as quenchers journal January 1985
New polynuclear U( iv )–U( v ) complexes from U( iv ) mediated uranyl( v ) disproportionation journal January 2012
Hydroxy- and alkoxy-bridged dinuclear uranyl–Schiff base complexes: hydrolysis, transamination and extraction studies journal January 2008
Recognition of Alkali Metal Halide Contact Ion Pairs by Uranyl−Salophen Receptors Bearing Aromatic Sidearms. The Role of Cation−π Interactions journal March 2005
Review Article: A Review of the Development and Operational Characteristics of the TALSPEAK Process journal October 2007

Cited By (3)

Tetrahydrosalen Uranyl(VI) Complexes: Crystal Structures and Solution Binding Study: Tetrahydrosalen Uranyl(VI) Complexes: Crystal Structures and Solution Binding Study journal March 2018
X-Ray crystallographic and computational study on uranyl–salophen complexes bearing nitro groups journal January 2017
Ligands for f-element extraction used in the nuclear fuel cycle journal January 2017

Similar Records

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY