Density functional theory study with and without COSMO of H2SO4 reactions in an aqueous environment for metal extraction

In a recent study investigating the suitability of solvent extraction (SX) for the separation of Ta and Nb, it was shown that speciation data would be required to help explain the data obtained. As traditional speciation techniques cannot be readily applied for Ta and Nb, it was decided to determine the suitability of molecular modeling for this purpose. During the SX experiments the aqueous phase consisted of sulfuric acid (H2SO4), water, and metal species.

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

[2]  L. Radom,et al.  An evaluation of harmonic vibrational frequency scale factors. , 2007, The journal of physical chemistry. A.

[3]  D. Neumark,et al.  Infrared Spectroscopy of Hydrated Bisulfate Anion Clusters: HSO4¯(H2O)1–16 , 2011 .

[4]  U. Landman,et al.  Structure and Energetics of Ionized Water Clusters: (H2O)n+, n = 2−5 , 1997 .

[5]  A. Becke.  A multicenter numerical integration scheme for polyatomic molecules , 1988 .

[6]  Reliable potential for small sulfuric acid–water clusters , 2003 .

[7]  K. Laasonen,et al.  Ab initio study of gas-phase sulphuric acid hydrates containing 1 to 3 water molecules , 1998 .

[8]  Burke,et al.  Generalized Gradient Approximation Made Simple. , 1996, Physical review letters.

[9]  M. Meuwly.  Theoretical and computational chemistry. , 2010, Chimia.

[10]  F. Yu,et al.  Theoretical analysis of the gas-phase hydration of common atmospheric pre-nucleation (HSO4-)(H2O)n and (H3O+)(H2SO4)(H2O)n cluster ions , 2009 .

[11]  Donald G. Truhlar,et al.  M11-L: A Local Density Functional That Provides Improved Accuracy for Electronic Structure Calculations in Chemistry and Physics , 2012 .

[12]  G. Harper,et al.  The Southern African Institute of Mining and Metallurgy Narrow Vein and Reef 2008 , 2009 .

[13]  A. Tkatchenko,et al.  Accurate molecular van der Waals interactions from ground-state electron density and free-atom reference data. , 2009, Physical review letters.

[14]  B. Delley.  Ground-state enthalpies: evaluation of electronic structure approaches with emphasis on the density functional method. , 2006, The journal of physical chemistry. A.

[15]  Partially and fully deprotonated sulfuric acid in H2SO4(H2O)n (n = 6-9) clusters , 2004 .

[16]  M. Kulmala,et al.  Quantum chemical studies of hydrate formation of H2SO4 and HSO4 , 2007 .

[17]  M. Shiga,et al.  Path-integral molecular dynamics simulations of small hydrated sulfuric acid clusters H2SO4·(H2O)n (n = 1–6) on semiempirical PM6 potential surfaces , 2009 .

[18]  A. Klamt,et al.  COSMO : a new approach to dielectric screening in solvents with explicit expressions for the screening energy and its gradient , 1993 .

[19]  Car,et al.  Unified approach for molecular dynamics and density-functional theory. , 1985, Physical review letters.

[20]  G. Walrafen,et al.  Infra-red absorption spectra of concentrated aqueous solutions of sulphuric acid. Part 2.—H2SO4 and HSO–4 vibrational fundamentals and estimates of (F°298·15—H°0)/T and S°298·15 for H2SO4 gas , 1961 .

[21]  V. Buch,et al.  Ab initio simulations of sulfuric acid solutions , 2008 .

[22]  Maohong Fan,et al.  Choosing a proper exchange-correlation functional for the computational catalysis on surface. , 2014, Physical chemistry chemical physics : PCCP.

[23]  C. Minot,et al.  Theoretical study of hydrated sulfuric acid: clusters and periodic modeling , 2005 .

[24]  Cory C. Pye,et al.  An ab Initio and Raman Investigation of Sulfate Ion Hydration , 2001 .

[25]  S. Donne,et al.  Electrochemical aspects of the Hybrid Sulfur Cycle for large scale hydrogen production , 2014 .

[26]  Friedhelm Bechstedt,et al.  Semiempirical van der Waals correction to the density functional description of solids and molecular structures , 2006 .

[27]  M. Samant,et al.  In-situ FT-IR spectroscopic study of bisulfate and sulfate adsorption on platinum electrodes: Part 1. Sulfuric acid , 1989 .

[28]  A. Williams-Jones,et al.  An experimental study of the solubility and speciation of 1 tantalum in fluoride-bearing aqueous solutions at elevated 2 temperature 3 4 , 2022 .

[29]  Huan-Cheng Chang,et al.  Infrared Spectra of H+(H2O)5-8 Clusters: Evidence for Symmetric Proton Hydration , 2000 .

[30]  Leo Radom,et al.  Harmonic Vibrational Frequencies: An Evaluation of Hartree−Fock, Møller−Plesset, Quadratic Configuration Interaction, Density Functional Theory, and Semiempirical Scale Factors , 1996 .

[31]  M. Shukla,et al.  Practical Aspects of Computational Chemistry II: An Overview of the Last Two Decades and Current Trends , 2012 .

[32]  J. Mccammon,et al.  Sulfate Anion in Water: Model Structural, Thermodynamic, and Dynamic Properties , 1994 .

[33]  P. Bourassa,et al.  Quantum chemical calculations of pristine and modified crystalline cellulose surfaces: benchmarking interactions and adsorption of water and electrolyte , 2014, Cellulose.

[34]  Mohd Bismillah Ansari,et al.  Sulfonic acid functionalized mesoporous ZSM-5: Synthesis, characterization and catalytic activity in acidic catalysis , 2015 .

[35]  H. Krieg,et al.  Comparison of extractants for the separation of TaF5 and NbF5 in different acidic media , 2014 .

[36]  K. Leopold,et al.  Microwave investigation of sulfuric acid monohydrate. , 2002, Journal of the American Chemical Society.

[37]  R. Krebs.  The History and Use of Our Earth's Chemical Elements: A Reference Guide , 2006 .

[38]  M. Czerwiński,et al.  Computational Chemistry in Modeling Solvent Extraction of Metal Ions , 2004 .

[39]  R. Ballardini,et al.  Experimental investigation of highly exergonic outer-sphere electron-transfer reactions , 1984 .

[40]  B. Delley,et al.  DMol, a standard tool for density functional calculations: Review and advances , 1995 .

[41]  K. Mikkelsen,et al.  Sulfuric Acid and Sulfuric Acid Hydrates in the Gas Phase: A DFT Investigation† , 2004 .

[42]  Wang,et al.  Accurate and simple analytic representation of the electron-gas correlation energy. , 1992, Physical review. B, Condensed matter.

[43]  William A Goddard,et al.  Evaluation of B3LYP, X3LYP, and M06-Class Density Functionals for Predicting the Binding Energies of Neutral, Protonated, and Deprotonated Water Clusters. , 2009, Journal of chemical theory and computation.

[44]  B. Delley,et al.  The conductor-like screening model for polymers and surfaces , 2006 .