On the properties of 1-butyl-3-methylimidazolium octylsulfate ionic liquid

This work reports on a theoretical and experimental study on the ionic liquid 1-butyl-3-methylimidazolium octylsulfate ([BMIM]OS). The halogen-free ionic liquid [BMIM]OS is a stable solvent regarding hydrolysis, whose availability, toxicologically favourable features and well documented biodegradability turns it into a suitable candidate for different multiton-scale industrial applications. The pressure–volume–temperature behaviour of this fluid has been evaluated accurately over wide ranges of temperature and pressure, and correlated successfully with the empirical TRIDEN equation. From the measured data the relevant derived coefficients, isothermal compressibility, isobaric expansibility and internal pressure have been calculated. Other valuable properties such as isobaric heat capacity, speed of sound and refractive index were measured at several temperatures and atmospheric pressure. The molecular structure was looked into by quantum computations at the B3LYP/6-31 + g(d) level and classical molecular dynamics simulations in the NPT ensemble with the OPLS–AA forcefield. Both macroscopic and microscopic studies concur in a complex structure involving microheterogenous polar and non-polar domains, brought about by the aggregation of the non-polar anionic chains.

[1]  Jürgen Gmehling,et al.  Densities of Toluene, Carbon Dioxide, Carbonyl Sulfide, and Hydrogen Sulfide over a Wide Temperature and Pressure Range in the Sub- and Supercritical State , 2001 .

[2]  Sandra Einloft,et al.  Synthesis and physical-chemical properties of ionic liquids based on 1-n-butyl-3-methylimidazolium cation , 1998 .

[3]  I. Cibulka.  Saturated liquid densities of 1-alkanols from C1 to c10 and n-alkanes from C5 to C16: A critical evaluation of experimental data , 1993 .

[4]  S. Dzyuba,et al.  Influence of structural variations in 1-alkyl(aralkyl)-3-methylimidazolium hexafluorophosphates and bis(trifluoromethyl-sulfonyl)imides on physical properties of the ionic liquids. , 2002, Chemphyschem : a European journal of chemical physics and physical chemistry.

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

[6]  A. Pensado,et al.  Volumetric behaviour of the environmentally compatible lubricants pentaerythritol tetraheptanoate and pentaerythritol tetranonanoate at high pressures , 2005 .

[7]  R. P. Swatloski,et al.  Efficient, halide free synthesis of new, low cost ionic liquids: 1,3-dialkylimidazolium salts containing methyl- and ethyl-sulfate anions , 2002 .

[8]  T. Darden,et al.  A smooth particle mesh Ewald method , 1995 .

[9]  J. Tojo,et al.  Temperature Dependence of Physical Properties of Ionic Liquid 1,3-Dimethylimidazolium Methyl Sulfate , 2006 .

[10]  A. Pádua,et al.  Modeling Ionic Liquids Using a Systematic All-Atom Force Field , 2004 .

[11]  Joan F. Brennecke,et al.  Volume Expansivities and Isothermal Compressibilities of Imidazolium and Pyridinium-Based Ionic Liquids , 2002 .

[12]  P. Scammells,et al.  Design and Preparation of Room-Temperature Ionic Liquids Containing Biodegradable Side Chains , 2002 .

[13]  Robin D. Rogers,et al.  Ionic liquids : industrial applications for green chemistry , 2002 .

[14]  M. Holz,et al.  Temperature-dependent self-diffusion coefficients of water and six selected molecular liquids for calibration in accurate 1H NMR PFG measurements , 2000 .

[15]  Huen Lee,et al.  Refractive index and heat capacity of 1-butyl-3-methylimidazolium bromide and 1-butyl-3-methylimidazolium tetrafluoroborate, and vapor pressure of binary systems for 1-butyl-3-methylimidazolium bromide + trifluoroethanol and 1-butyl-3-methylimidazolium tetrafluoroborate + trifluoroethanol , 2004 .

[16]  M. Shara,et al.  Neoteric optical media for refractive index determination of gems and minerals , 2006 .

[17]  Vincenzo Barone,et al.  Inclusion of Hartree-Fock exchange in the density functional approach. Benchmark computations for diatomic molecules containing H, B, C, N, O, and F atoms , 1994 .

[18]  K. Marsh,et al.  Room temperature ionic liquids and their mixtures—a review , 2004 .

[19]  M. Taravillo,et al.  Thermodynamic regularities in compressed liquids: I. The thermal expansion coefficient , 2003 .

[20]  J. Brennecke,et al.  Ionic liquids: Innovative fluids for chemical processing , 2001 .

[21]  M. Dack.  The importance of solvent internal pressure and cohesion to solution phenomena , 1975 .

[22]  James H. Davis,et al.  From curiosities to commodities: ionic liquids begin the transition. , 2003, Chemical communications.

[23]  Mary Jane Hale,et al.  Advanced Thermal Storage Fluids for Solar Parabolic Trough Systems , 2002 .

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

[25]  E. Maginn,et al.  A Monte Carlo simulation study of the ionic liquid 1-n-butyl-3-methylimidazolium hexafluorophosphate: liquid structure, volumetric properties and infinite dilution solution thermodynamics of CO2 , 2004 .

[26]  C. Pretti,et al.  Acute toxicity of ionic liquids to the zebrafish (Danio rerio) , 2006 .

[27]  A. Goodwin,et al.  Measurement of the Viscosity and Density of Two Reference Fluids, with Nominal Viscosities at T = 298 K and p = 0.1 MPa of (16 and 29) mPa·s, at Temperatures between (298 and 393) K and Pressures below 55 MPa , 2005 .

[28]  P. Wasserscheid,et al.  1-n-Butyl-3-methylimidazolium ([bmim]) octylsulfate—an even ‘greener’ ionic liquid , 2002 .

[29]  K. Cox.  Physical Property needs in Industry , 1993 .

[30]  Analysis of solvation in ionic liquids using a new linear solvation energy relationship , 2005 .

[31]  Wenchuan Wang,et al.  A refined force field for molecular simulation of imidazolium-based ionic liquids , 2004 .

[32]  José Mario Martínez,et al.  Packing optimization for automated generation of complex system's initial configurations for molecular dynamics and docking , 2003, J. Comput. Chem..

[33]  Robin D. Rogers,et al.  Characterization and comparison of hydrophilic and hydrophobic room temperature ionic liquids incorporating the imidazolium cation , 2001 .

[34]  P. Wasserscheid,et al.  Journal of the Royal Institute of Chemistry. November 1959 , 1959 .

[35]  A. Becke,et al.  Density-functional exchange-energy approximation with correct asymptotic behavior. , 1988, Physical review. A, General physics.

[36]  H. Pauly,et al.  Pycnometric vs. densimetric measurements of highly viscous protein solutions , 1980 .

[37]  M. Nunes da Ponte,et al.  A detailed thermodynamic analysis of [C4mim][BF4]+ water as a case study to model ionic liquid aqueous solutions , 2004 .

[38]  J. Brennecke,et al.  Thermodynamic properties of the ionic liquid 1-n-butyl-3-methylimidazolium hexafluorophosphate from Monte Carlo simulations , 2002 .

[39]  A. Klamt,et al.  Room temperature ionic liquids as replacements for conventional solvents – A review , 2002 .

[40]  M. Bühl,et al.  Ab initio molecular dynamics of liquid 1,3-dimethylimidazolium chloride. , 2005, The journal of physical chemistry. B.

[41]  E. Maginn,et al.  Molecular Dynamics Study of the Ionic Liquid 1-n-Butyl-3-methylimidazolium Hexafluorophosphate , 2002 .

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

[43]  J. Rubin,et al.  Calculation of Hansen Solubility Parameter Values for a Range of Pressure and Temperature Conditions, Including the Supercritical Fluid Region , 2004 .

[44]  G. Voth,et al.  On the Structure and Dynamics of Ionic Liquids , 2004 .

[45]  S. Aparicio,et al.  PVTx measurements of the N-methylpyrrolidone/methanol mixed solvent: cubic and SAFT EOS analyses. , 2006, The journal of physical chemistry. B.

[46]  J. Esperança,et al.  Thermophysical and thermodynamic properties of ionic liquids over an extended pressure range : [bmim][NTf2] and [hmim][NTf2] , 2005 .

[47]  Vesna Najdanovic-Visak,et al.  Thermophysical and Thermodynamic Properties of 1-Butyl-3-methylimidazolium Tetrafluoroborate and 1-Butyl-3-methylimidazolium Hexafluorophosphate over an Extended Pressure Range , 2005 .

[48]  E. Carballo,et al.  Highly precise determination of the heat capacity of liquids by DSC: calibration and measurement , 2000 .

[49]  G. Voth,et al.  Unique spatial heterogeneity in ionic liquids. , 2005, Journal of the American Chemical Society.

[50]  B. Berne,et al.  Computer simulation of a green chemistry room-temperature ionic solvent , 2002 .

[51]  P. Scammells,et al.  Biodegradable ionic liquids Part II. Effect of the anion and toxicology , 2005 .

[52]  A. Pádua,et al.  Nanostructural organization in ionic liquids. , 2006, The journal of physical chemistry. B.

[53]  Philip R. Watson,et al.  Surface Tension Measurements of N-Alkylimidazolium Ionic Liquids , 2001 .

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

[55]  U. Essmann,et al.  Simulation of Sodium Dodecyl Sulfate at the Water−Vapor and Water−Carbon Tetrachloride Interfaces at Low Surface Coverage , 1997 .

[56]  R. Onodera,et al.  In Vitro Catabolism of Histidine by Mixed Rumen Bacteriaand Protozoa , 2001, Current Microbiology.

[57]  Robin D. Rogers,et al.  Ionic liquids are not always green: hydrolysis of 1-butyl-3-methylimidazolium hexafluorophosphate , 2003 .

[58]  Manuel Berenguel,et al.  Advanced control of solar plants , 1997 .

[59]  Huen Lee,et al.  Physical and electrochemical properties of 1-butyl-3-methylimidazolium bromide, 1-butyl-3-methylimidazolium iodide, and 1-butyl-3-methylimidazolium tetrafluoroborate , 2004 .

[60]  Sang Hyun Lee,et al.  The Hildebrand solubility parameters, cohesive energy densities and internal energies of 1-alkyl-3-methylimidazolium-based room temperature ionic liquids. , 2005, Chemical communications.

[61]  S. Aparicio,et al.  Solute-solvent interactions in lactams-water ternary solvents , 2005 .

[62]  J. Turner,et al.  Density measurement by oscillating tube. Effects of viscosity, temperature, calibration and signal processing , 1990 .

[63]  A. McLean,et al.  Estimates of internal energies of vaporisation of some room temperature ionic liquids. , 2004, Chemical communications.

[64]  M. Holz,et al.  Biological applications of scanning tunnelling microscopy , 1993 .

[65]  Johan Jacquemin,et al.  Density and viscosity of several pure and water-saturated ionic liquids , 2006 .

[66]  Nicholas Gathergood,et al.  Biodegradable ionic liquids: Part I. Concept, preliminary targets and evaluation , 2004 .