Solvation of the Ca 2 UO 2 (CO 3 ) 3 Complex in Seawater from Classical Molecular Dynamics

: Uranium from the sea provides a long-time supply guarantee of nuclear fuels for centuries to come, and the neutral Ca 2 UO 2 (CO 3 ) 3 complex has been shown to be the dominant species of uranium in seawater. However, the solvation and structure of the Ca 2 UO 2 (CO 3 ) 3 complex in seawater have been unclear. Herein we simulate the Ca 2 UO 2 (CO 3 ) 3 complex in a model seawater solution via classical molecular dynamics. We fi nd that Na + and Cl − ions interact very di ff erently with the neutral Ca 2 UO 2 (CO 3 ) 3 complex in seawater. Especially, one Na + ion is closely associated with the Ca 2 UO 2 (CO 3 ) 3 complex, thereby e ff ectively making the complex have a +1 charge, while Cl − ions are much farther away. Hence, this work reveals the important role of Na + ions in a ff ecting the solvation of the Ca 2 UO 2 (CO 3 ) 3 complex in seawater, which has implications in designing ligands to attract the Ca 2 UO 2 (CO 3 ) 3 complex to the sorbent.

[1]  D. Jiang,et al.  First-principles molecular dynamics simulation of the Ca2UO2(CO3)3 complex in water. , 2016, Dalton transactions.

[2]  C. Tsouris,et al.  Alternative Alkaline Conditioning of Amidoxime Based Adsorbent for Uranium Extraction from Seawater , 2016 .

[3]  T. Hofer,et al.  The structural influence of Ca(2+) counter-ions on uranyl(VI) tricarbonate in aqueous solution. , 2016, Dalton transactions.

[4]  R. Mayes,et al.  XAFS investigation of polyamidoxime-bound uranyl contests the paradigm from small molecule studies , 2016 .

[5]  Yundong Wu,et al.  A diversity-oriented synthesis of bioactive benzanilides via a regioselective C(sp2)–H hydroxylation strategy , 2015, Chemical science.

[6]  N. Mehio,et al.  Theoretical study of the coordination behavior of formate and formamidoximate with dioxovanadium(V) cation: implications for selectivity towards uranyl. , 2015, Physical chemistry chemical physics : PCCP.

[7]  L. Rao,et al.  Chemical speciation of uranium(VI) in marine environments: complexation of calcium and magnesium ions with [(UO2 )(CO3 )3 ](4-) and the effect on the extraction of uranium from seawater. , 2014, Chemistry.

[8]  R. Rogers,et al.  Structural clues to UO₂²⁺/VO₂⁺ competition in seawater extraction using amidoxime-based extractants. , 2014, Chemical communications.

[9]  C. Tsouris,et al.  Uptake of Uranium from Seawater by Amidoxime-Based Polymeric Adsorbent: Field Experiments, Modeling, and Updated Economic Assessment , 2014 .

[10]  L. Rao,et al.  Quantifying the binding strength of U(VI) with phthalimidedioxime in comparison with glutarimidedioxime. , 2014, Dalton transactions.

[11]  T. Hofer,et al.  A comparative quantum mechanical charge field study of uranyl mono- and dicarbonate species in aqueous solution. , 2013, The journal of physical chemistry. B.

[12]  Shubin Liu,et al.  Tuning amidoximate to enhance uranyl binding: a density functional theory study. , 2013, The journal of physical chemistry. A.

[13]  B. Hay,et al.  De novo structure-based design of bis-amidoxime uranophiles. , 2013, Inorganic chemistry.

[14]  Erich A Schneider,et al.  Recovery of Uranium from Seawater: A Review of Current Status and Future Research Needs , 2013 .

[15]  Jian-ying Qi,et al.  Surface Water Contamination by Uranium Mining/Milling Activities in Northern Guangdong Province, China , 2012 .

[16]  Zhiyong Zhang,et al.  Sequestering uranium from seawater: binding strength and modes of uranyl complexes with glutarimidedioxime. , 2012, Dalton transactions.

[17]  R. Custelcean,et al.  How amidoximate binds the uranyl cation. , 2012, Inorganic chemistry.

[18]  N. Burton,et al.  Investigation of ligand exchange reactions in aqueous uranyl carbonate complexes using computational approaches. , 2011, Physical chemistry chemical physics : PCCP.

[19]  S. Kerisit,et al.  Molecular Simulation of the Diffusion of Uranyl Carbonate Species in Aqueous Solution , 2010 .

[20]  P. Rentzepis,et al.  Bond evolution in electron transfer: a time-resolved EXAFS study. , 2010, The journal of physical chemistry. A.

[21]  J. Love,et al.  Pentavalent uranyl complexes , 2009 .

[22]  T. Cheatham,et al.  Determination of Alkali and Halide Monovalent Ion Parameters for Use in Explicitly Solvated Biomolecular Simulations , 2008, The journal of physical chemistry. B.

[23]  Junmei Wang,et al.  Development and testing of a general amber force field , 2004, J. Comput. Chem..

[24]  J. de Pablo,et al.  DFT studies of uranyl acetate, carbonate, and malonate, complexes in solution. , 2003, Inorganic chemistry.

[25]  G. A. Parks,et al.  XAFS spectroscopic study of uranyl coordination in solids and aqueous solution , 1997 .

[26]  V. Brendler,et al.  Speciation of Uranium in Seepage Waters of a Mine Tailing Pile Studied by Time-Resolved Laser-Induced Fluorescence Spectroscopy (TRLFS) , 1996 .

[27]  G. Meinrath.  Coordination of uranyl(VI) carbonate species in aqueous solutions , 1996 .

[28]  G. Wipff,et al.  Force field representation of the UO22+ cation from free energy MD simulations in water. Tests on its 18-crown-6 and NO3− adducts, and on its calix[6]arene6− and CMPO complexes , 1996 .

[29]  S. Shaik,et al.  Ab initio calculations for small iodo clusters. Good performance of relativistic effective core potentials , 1995 .

[30]  Steve Plimpton,et al.  Fast parallel algorithms for short-range molecular dynamics , 1993 .

[31]  A. Becke.  Density-functional thermochemistry. III. The role of exact exchange , 1993 .

[32]  G. D. Price,et al.  Interatomic potentials for CaCO3 polymorphs (calcite and aragonite), fitted to elastic and vibrational data , 1992 .

[33]  Parr,et al.  Development of the Colle-Salvetti correlation-energy formula into a functional of the electron density. , 1988, Physical review. B, Condensed matter.

[34]  Hoover,et al.  Canonical dynamics: Equilibrium phase-space distributions. , 1985, Physical review. A, General physics.

[35]  Masayoshi Kanno,et al.  Present Status of Study on Extraction of Uranium from Sea Water , 1984 .

[36]  W. L. Jorgensen,et al.  Comparison of simple potential functions for simulating liquid water , 1983 .

[37]  G. Ciccotti,et al.  Numerical Integration of the Cartesian Equations of Motion of a System with Constraints: Molecular Dynamics of n-Alkanes , 1977 .

[38]  P. C. Hariharan,et al.  The influence of polarization functions on molecular orbital hydrogenation energies , 1973 .

[39]  D. Love,et al.  Radiochemical Determination of Sodium-24 and Sulfur-35 in Seawater. , 1962 .

[40]  Jing Chen,et al.  New insights into the uranium adsorption behavior of mesoporous SBA-15 silicas decorated with alkylphosphine oxide ligands , 2016 .

[41]  S. Brooks,et al.  X-ray absorption spectroscopy identifies calcium-uranyl-carbonate complexes at environmental concentrations☆ , 2007 .

[42]  Á. Pérez‐Jiménez,et al.  Electronic transport in molecular nanodevices from ab-initio calculations , 2005 .

[43]  G. Bernhard,et al.  Uranyl(VI) carbonate complex formation: Validation of the Ca2UO2(CO3)3(aq.) species , 2001 .

[44]  T. Kawakami,et al.  Adsorption of Uranium in Sea Water Using Amidoxime Adsorbents Prepared by Radiation-Induced Cografting. , 1998 .

[45]  S. C. Parker,et al.  Atomistic simulation of the effect of molecular adsorption of water on the surface structure and energies of calcite surfaces , 1997 .

[46]  K. Kusakabe,et al.  Preparation and performance of amidoxime fiber adsorbents for recovery of uranium from seawater , 1992 .