Thermophysical Properties of 1-Butyl-3-methylimidazoliurn Trifluoromethanesulfonate in a Wide Range of Temperatures and Pressures

(p,rho,T) data of 1-butyl-3-methylimidazolium trifluoromethanesulfonate [BMIM] [TFO] are reported, obtained using an Anton-Paar DMA HPM vibration tube densimeter. The measurements were conducted at T = (283.15 to 413.15) K and p = (0.101 to 140) MPa. The combined uncertainty at 0.95 level of confidence of a density measurement is estimated up to U-c(rho) = 0.8 kg.m(-3). An equation of state for fitting of the (p,rho,T) data of [BMIM][TFO] has been developed as a function of pressure and temperature. The equation of state is constructed for the fitted experimentally investigated (p,rho,T) values, and various thermophysical properties such as isothermal compressibility, isobaric thermal expansivity, thermal pressure coefficient, internal pressure, heat capacities at constant pressure and volume, speed of sound, and isentropic exponent at this temperature and pressure intervals were calculated.