Measurement of the Viscosity,Density,and Electrical Conductivity of 1-Hexyl-3-methylimidazolium Bis(trifluorosulfonyl)imide at Temperatures between(288 and 433)K and Pressures below 50 MPa

摘要

The viscosity,density,and electrical conductivity of 1-hexyl-3-methylimidazolium bis(trifluorosulfonyl)imide have been measured at temperatures from(288 to 433)K and at pressures up to 50 MPa.A vibrating wire viscometer was used for the measurements of viscosity that have an expanded uncertainty(k=2)of±2%.The density was obtained from a vibrating tube densimeter with an expanded uncertainty(k=2)of±0.3%.The electrical conductivity k(f->infinity)was determined from impedance measurements at frequencies in the range(0.5 to 10)kHz with an expanded(k=2)uncertainty of±2%.All measurements were conducted with a sample distributed by NIST as part of an IUPAC project.The water mass fraction was determined before and after the measurements.The viscosity and density of a sample with initial water content of 7·10~(-6)were represented by interpolating expressions with standard deviations of 0.4% and 0.03%,respectively.Differences between the experimental and calculated values are comparable with the expanded(k=2)uncertainties.For temperatures that overlap the temperature range(288 to 433)K at p=0.1 MPa,literature values of density differ by<=±0.2% while the reported viscosities differ by<±7% from these empirical representations of the measurements.There are no values of the viscosity at p>0.1 MPa reported in the literature to compare our results.At p>0.1 MPa,the literature values for density reported by Gomes de Azevedo(J.Chem.Thermodyn.2005,37,888-899)deviate from our smoothing equation by less than-0.2% at temperatures and pressure that overlap ours.The electrical conductivity was determined on a sample with initial water mass fraction of 90-10~6.The results were represented within the expanded uncertainty by an empirical function against which the literature values differed by no more than±5%.