Thermophysical Properties of 1-Butyl-3-methylimidazolium

Article Cite This: J. Chem. Eng. Data XXXX, XXX, XXX−XXX

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Thermophysical Properties of 1‑Butyl-3-methylimidazolium Trifluoromethanesulfonate in a Wide Range of Temperatures and Pressures Javid Safarov,*,† Aytakin Guluzade,‡ and Egon Hassel† †

Institute of Technical Thermodynamics, University of Rostock, Albert-Einstein-Str. 2, D-18059 Rostock, Germany Department of Heat Energy, Azerbaijan Technical University, H. Javid Avn. 25, AZ1073 Baku, Azerbaijan

‡

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S Supporting Information *

ABSTRACT: (p,ρ,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 Uc(ρ) = 0.8 kg·m−3. An equation of state for fitting of the (p,ρ,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,ρ,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.

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installations, have already been published.5,6 These results, together with (p,ρ,T) results, allow for the calculation of different thermophysical properties, like isothermal compressibility κT(p,T), isobaric thermal expansivity αp(p,T), thermal pressure coefficient γ(p,T), internal pressure pint(p,T), specific heat capacities cp(p,T) and cv(p,T), speed of sound u(p,T), and isentropic exponent κs(p,T) at a wide range of temperatures and high pressures. For this purpose, the equation of state (EOS) was established. Information about literature density ρ (kg·m−3) investigations of [BMIM][TFO] at ambient pressure ρ(p0,T) and its (p,ρ,T) data7−33 is presented in Table 1: Fredlake et al.7 investigated the density and heat capacity of [BMIM][TFO] at temperature T = (295.75 to 342.95) K and ambient pressures using 1 mL pycnometers from Thomas Scientific. Tokuda et al.8,9 studied the density of [BMIM][TFO] at temperature T = (288.15 to 313.15) K and at atmospheric pressure using the thermoregulated density/specific gravity meter DA-100. ́ Garcia-Miaja et al.11 investigated the density of [BMIM][TFO] at p = 0.101 MPa and T = (293.15 to 318.15) K using an Anton-Paar DMA 5000 vibrating tube densimeter. Ge et al.12 studied the density of [BMIM][TFO] at T = (303.15 to 343.15) K and at atmospheric pressure. Jacquemin et al.13 studied the densities of [BMIM][TFO] at T = (293.15 to 363.15) K at ambient pressure using the Anton-Paar DMA 512 vibrating tube densimeter. McHale et al.,14 Tariq et al.,17 and

INTRODUCTION Ionic liquids (ILs) have great importance due to their thermophysical and chemical properties (i.e., very small vapor pressure, large liquidus range, non-flammability, etc.). These properties make ILs popular substances within the chemical and mechanical engineering industries, specifically in catalytic biomass transformation, solvation technology, electronics, Liion batteries, the polymer industry, separation technology, and liquid−liquid extraction.1−3 Thermophysical and electrochemical properties are important for the analysis and application of ILs. The most fundamental properties of ILs are (p,ρ,T) data, which are experimentally measured and presented in this paper. Additionally, the viscosity, heat capacity, and speed of sound are also investigated, from which more thermophysical parameters can be derived. For this reason, (p,ρ,T) dependence is the primary investigated property within this research. This work is a continuation of determining IL thermophysical properties at the high state parameter (p,T) interval, using their density values at high state parameters and experimental heat capacity cp(p0,T) values at ambient pressure.4 In this paper, the (p,ρ,T) properties of 1-butyl-3-methylimidazolium trifluoromethanesulfonate [BMIM][TFO] at a wide T = (283.15 to 413.15) K temperature interval and high pressures (up to p = 140 MPa) were studied for the first time using a high quality DMA HPM vibrating tube densimeter from AntonPaar. The heat capacity cp(p0,T), speed of sound u(p0,T), and viscosity η(p0,T) of [BMIM][TFO], measured using a Pyris 1 differential scanning calorimeter (DSC), Anton-Paar DSA 5000M, SVM 3000 Stabinger, and Rheometer MCR 302 © XXXX American Chemical Society

Received: September 19, 2018 Accepted: March 22, 2019

A

DOI: 10.1021/acs.jced.8b00837 J. Chem. Eng. Data XXXX, XXX, XXX−XXX

B

2004 2004 2006 2007 2008 2008 2008 2008 2009 2009 2009 2009 2010 2010 2010 2011 2012 2012 2012 2012 2013 2014 2014 2015 2016 2016 2017 2018

year

PC TRDSG VTD VTD VTD PC VTD QCM VTD VTD VTD MDT TBM VTD VTD VTD VTD CVP VTD VTD VTD VTD VTD VTD VTD VTD VTD VTD

method ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, ρ, T, cp T, η, σ T, η, σ p, T T, cp, u T, η T T, η T, cp, u, VE T, η T, σ T T T, η, σ T T, u, nD T, u, nD T, P T, η, u T, η, u T, u, cp T, η, VE T, η T, nD T, η T, η T, η, σ p, T

properties 295.75 to 342.95 288.15 to 313.15 288.15 to 313.15 293.15 to 393.15 293.15 to 318.15 303.15 to 343.15 293.15 to 363.15 298.15 293.15 to 318.15 298.2 to 353.2 293.15 to 333.15 303 292.94 to 355.85 283.15 to 363.15 278.15 to 338.15 298.15 288.15 to 308.15 290.497 to 350.378 293.15 to 343.15 288.15 to 338.15 293.15 to 323.15 298.15 to 328.15 297.98 to 343.12 293.15 to 343.15 298.15 298.15 to 323.15 303.15 to 323.15 283.15 to 413.15

temperature T (K) 0.101 0.101 0.101 0.10 to 10 0.101 0.101 0.101 NA 0.101 0.101 0.101 0.101 0.101 0.101 0.101 0.101 0.101 0.2411 to 60.046 0.101 0.101 0.101 0.101 0.101 0.101 0.101 0.101 0.101 0.101 to 140

pressure p (MPa) 0.5% NA NA ±1 kg·m−3 ±0.1 kg·m−3 ±0.1 kg·m−3 NA 0.48% ±0.1 kg·m−3 ±0.4 kg·m−3 ±0.04 kg·m−3 >1% ±0.1 to 0.2 kg·m−3 ±0.2 kg·m−3 0.999 w > 0.99 NA NA 1.3 × 10−3 w.m.f. ≥0.981 NA NA 0.99 NA 80 × 10−6 w.m.f. xw < 0.0005 >0.99 0.99 w > 0.99 >0.98 >0.999 w > 0.99 0.995 mole fr. 15 ppm 14 ppm ≥0.98 w.f. 98% 40 ppm

purity

Aldrich LP NA SI Scharlau LP LP NA SI TCI Co QUILL NA Merck, Solvionic Merck LP SI IoLiTec Solvionic IoLiTec SI IoLiTec IoLiTec IoLiTec IoLiTec IoLiTec SA SA Merck

company of purchase

PC, pycnometer; ρ, density; T, temperature; TRDSG; thermoregulated density/specific gravity meter; η, viscosity; σ, surface tension; VTD, vibrating tube densitometer; LP, laboratory product; NA, not available; cp, heat capacity at constant pressure; u, speed of sound; QCM, quartz crystal method; MDT, MD trajectories; TBM, the buoyancy method; nD, refractive index; SI, Solvent Innovation; SA, Sigma-Aldrich; CVP, constant volume piezometer; cp, heat capacity; VE, excess molar volume; w.m.f., weight mass fraction; mole fr., mole fraction; p.w., present work; BRES, Baku−Rostock equation of state.

a

Soriano16 Tariq17 Tsuzuki18 Klomfar19 Shamsipur20 Zech21 Vercher22 Gonzalez23 Klomfar24 Seoane25 Vercher26 Gonzalez27 Batista28 Tsamba29 Montalbán30 Andanson31 Anwar32 Khan33 Safarovp.w.

Fredlake Tokuda8 Tokuda9 Gardas10 11 ́ Garcia-Miaja Ge12 Jacquemin13 McHale14 15 ́ Garcia-Miaja

7

reference

Table 1. Summary of the Thermophysical Properties of [BMIM][TFO]a

Journal of Chemical & Engineering Data Article


Journal of Chemical & Engineering Data

Article

Khan et al.33 used a DMA 4500 vibrating tube densimeter to study the [BMIM][TFO] densities at T = 298.15, T = (293.15 to 333.15), and T = (303.15 to 323.15) K, respectively. ́ Garcia-Miaja et al.15 and Andanson et al.31 used an AntonPaar DMA5000 vibrating tube densimeter for the measurements of [BMIM][TFO] densities at ambient pressure and temperatures T = (293.15 to 318.15) and T = 298.15 K, respectively. Soriano et al.,16 Shamsipur et al.,20 and Batista et al.28 used the same SVM 3000 Stabinger viscometer model for studying the densities of [BMIM][TFO] at p = 0.101 MPa and at T = (298.2 to 353.2), T = (283.15 to 363.15), at T = (298.15 to 328.15) K, respectively. Tsuzuki et al.18 calculated the density of [BMIM][TFO] at T = 303 K and ambient pressure, where the density results from Tokuda et al.8,9 were used during the calculation. Klomfar et al.19 studied the densities of [BMIM][TFO] at ambient pressure and temperatures at T = (292.94 to 355.85) K. Seoane et al.,25 Gonzalez et al.,27 and Anwar and Riyazuddeen32 presented the densities of [BMIM][TFO] at ambient pressure using an Anton-Paar DSA 5000M density and sound velocity meter at T = (293.15 to 343.15), T = (293.15 to 323.15), and T = (298.15 to 323.15) K, respectively. Additionally, Zech et al.,21 Vercher et al.,22,26 Gonzalez et al.,23 Tsamba et al.,29 and Montalbán et al.30 used a vibrating tube densimeter to measure ambient pressure densities of [BMIM][TFO] at [T = (278.15 to 338.15), T = 298.15, T = (288.15 to 338.15), T = (288.15 to 308.15), T = (297.98 to 343.12), and T = (293.15 to 343.15) K, respectively]. There are only two high pressure density investigations of [BMIM][TFO] in the literature. First, Gardas et al.10 measured the (p,ρ,T) data at T = (293.15 to 393.15) K and pressures p = (0.10 to 10.0) MPa. They used an Anton-Paar DMA 60 digital vibrating tube densimeter with a DMA 512P measuring cell. The Tait type EOS was used during the fitting. The thermal properties were calculated. Second, Klomfar et al.24 analyzed the densities of [BMIM][TFO] at T = (290.497 to 350.378) K and p = (0.2411 to 60.046) MPa in an isochoric piezometer apparatus. Analysis of the literature reveals7−33 the necessity for careful experimental investigations of the high pressure-high temperature densities of [BMIM][TFO] and analysis of derived properties because (1) there are no density values above 60 MPa, (2) there are no density values above T = 393.15 K at high pressures, and (3) there are no thermophysical properties at high state parameters.

Table 3. Measured at p0 = 0.101 MPa in an Anton-Paar DSA 5000M, DMA 5000M (353.15 K) Density ρ(p0,T) Values of [BMIM][TFO] T (K) a

283.15 288.15 293.15 298.15 303.15 313.13 333.15 343.15 353.15 373.15 393.15 413.15

ρ (kg·m−3) 1309.81 1305.77 1301.75 1297.74 1293.74 1285.81 1270.09 1262.32 1254.61 1239.37 1224.37 1209.60

a Standard uncertainty u are u(T) = 0.015 K, u(p = 0.101 MPa) = 0.5% and the combined expanded uncertainty Uc is Uc(ρ) = 0.3 kg·m−3 for 283.15 K < T < 343.15 K, Uc(ρ) = 0.8 kg·m−3 for T > 353.15 K (0.95 level of confidence).

1-Butyl-3-methylimidazolium trifluoromethanesulfonate. bKF, KarlFischer titration.

under a vacuum for 48 h at a temperature T of 423.15 K. The mass fraction of water was determined after drying by means of Karl-Fischer titration and was less than 140 ppm. The ambient pressure densities of [BMIM][TFO] are necessary in order to check the accuracy of the investigated high pressure-high temperature (p,ρ,T) data using the small extrapolation to p = 0.101 MPa. They were measured in the temperature range T = (283.15 to 413.15) K using Anton-Paar DMA 5000M, DSA 5000M, and DMA HPM vibrating tube densimeters with an uncertainty up to Δρ = ±0.3 kg·m−3. The densimeters DSA 5000M and DMA 5000M (except DMA HPM) used to measure the density at atmospheric pressure include an automatically correcting effect of viscosity on the measured density values. The physical bases of all these densimeters are the same, with differences only in some improvements made by the manufacturer, which results in an increase in the accuracy of the thermostat (temperature control and sample temperature measurements) when using new electronics and material and optimal size of the tubes. For example, the modern DSA 5000M is a vibrating tube sound analyzer and densimeter with a certified precision of Δρ = ±5 ×·10−3 kg·m−3. The density at T = (283.15 to 413.15) K and p = (0.101 to 140) MPa was investigated using an Anton-Paar DMA HMP vibrating tube densimeter.34,35 The temperature in the measuring cell was controlled using a thermostat within 10 mK and was measured with an absolute uncertainty of 15 mK. Pressure was measured using a pressure transmitter P-30 (0.25, 2.5, 50, 100 MPa) with an uncertainty of 0.1% and HP-1 (160 MPa) with an uncertainty of 0.5%. The observed repeatability of the density measurements at temperatures T = (263.15 to 468.55) K and pressures up to p = 140 MPa is within up to 0.3 kg·m−3; average expanded relative uncertainty is within up to 0.03%. Viscosity corrections were necessary36−40 if the sample has high viscosity ρHPM − ρ = (0.4482 η − 0.1627) × 10−4 ρHPM (1)

purity ≥99%, Mw = 0.28829 kg·mol−1) was received from Merck. In order to remove all volatile impurities, the sample was dried

where ρHPM is the density obtained from measurements, ρ is the corrected densities, and η(p,T) (mPa·s) is the viscosity of [BMIM][TFO].

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EXPERIMENTAL SECTION [BMIM][TFO] (Table 2) (CAS: 174899-66-2, chemical formula C9H15F3N2O3S (Figure S1), product number 4900240100, Table 2. Specifications of Chemical Sample chemical name [BMIM] [TFO]a

source Merck AG

initial mole fraction purity

final mole fraction purity

analysis method

0.98

0.99

KFb

a

C



Article

Table 4. Experimental Values of Pressure p, Density ρ, Temperature T, Calculated Values of Isothermal Compressibility κT × 106, Isobaric Thermal Expansivity αp × 106, Difference in Isobaric and Isochoric Heat Capacities (cp − cv), Thermal Pressure Coefficient γ, Internal Pressure pint, Isobaric Heat Capacity cp, Isochoric Heat Capacity cv, Speed of Sound u, and Isentropic Exponent κs of 1-Butyl-3-methylimidazolium Trifluoromethanesulfonate [BMIM][TFO] p (MPa) 0.101 1.225 5.337 9.906 20.345 29.997 40.094 49.996 60.363 69.993 79.621 90.097 100.086 109.957 119.997 129.993 139.996 0.101 1.740 4.978 9.722 20.425 29.997 40.322 49.997 60.340 69.996 80.507 89.996 100.028 109.846 119.150 129.846 138.949 0.101 1.023 5.026 10.006 19.968 30.005 40.008 49.962 59.968 70.005 79.986 90.001 99.997 109.968 120.001 130.002 139.996 0.101 1.097 5.364 10.395 20.326 29.996

a

ρ (kg·m−3)

T (K)

κT (MPa−1)

αp (K−1)

1309.80 1310.35 1312.37 1315.03 1320.61 1325.60 1330.63 1335.42 1340.27 1344.64 1348.88 1353.37 1357.13 1361.36 1365.53 1369.54 1373.39 1301.72 1302.55 1304.20 1307.00 1312.86 1317.90 1323.16 1327.93 1332.87 1337.34 1342.04 1346.17 1350.06 1354.33 1358.24 1362.58 1366.14 1297.80 1298.28 1300.40 1303.37 1308.89 1314.25 1319.41 1324.37 1329.20 1333.89 1338.41 1342.82 1347.10 1351.04 1355.27 1359.35 1363.31 1285.70 1286.27 1288.67 1291.48 1296.92 1302.11

283.15 283.17 283.15 283.15 283.14 283.15 283.17 283.16 283.16 283.16 283.16 283.15 283.15 283.15 283.15 283.15 283.15 293.15 293.20 293.20 293.15 293.15 293.15 293.16 293.15 293.16 293.15 293.17 293.15 293.16 293.15 293.15 293.15 293.15 298.15 298.15 298.16 298.15 298.15 298.13 298.15 298.15 298.14 298.15 298.15 298.13 298.15 298.15 298.15 298.16 298.15 313.15 313.20 313.20 313.15 313.15 313.15

421.9 420.1 413.5 406.4 391.1 378.1 365.5 354.0 342.7 333.0 323.8 314.4 306.0 298.2 290.6 283.5 276.8 436.3 433.5 428.0 420.0 403.3 389.6 375.9 363.9 352.1 341.7 331.2 322.3 313.5 305.3 297.9 290.0 283.5 443.8 442.2 435.0 426.4 410.4 395.5 381.8 369.1 357.3 346.2 336.0 326.3 317.2 308.7 300.6 293.0 285.8 467.4 465.5 457.0 447.3 429.6 413.8

626.4 624.9 619.3 613.2 600.3 589.1 578.2 568.2 558.4 549.9 541.8 533.5 526.0 519.0 512.3 505.9 499.8 626.2 623.8 619.2 612.5 598.5 586.9 575.2 565.0 554.8 545.9 536.8 529.1 521.3 514.2 507.8 500.8 495.1 625.8 624.4 618.5 611.4 598.0 585.5 574.0 563.3 553.3 543.9 535.2 526.9 519.2 511.9 504.9 498.4 492.2 622.6 621.0 614.2 606.7 592.6 580.1

γ (cp − cv) (J·kg−1·K−1) (MPa·K−1) 201.0 200.8 200.1 199.2 197.5 196.0 194.7 193.4 192.2 191.2 190.3 189.4 188.6 187.9 187.2 186.6 186.1 202.4 202.1 201.4 200.4 198.3 196.7 195.0 193.7 192.3 191.2 190.1 189.1 188.3 187.5 186.8 186.1 185.5 202.7 202.5 201.6 200.5 198.5 196.7 195.1 193.6 192.3 191.1 190.0 189.0 188.1 187.3 186.6 185.9 185.3 202.0 201.7 200.7 199.5 197.3 195.5

1.4846 1.4874 1.4977 1.5090 1.5347 1.5579 1.5819 1.6053 1.6293 1.6514 1.6732 1.6968 1.7190 1.7407 1.7626 1.7842 1.8056 1.4352 1.4389 1.4468 1.4585 1.4839 1.5064 1.5303 1.5525 1.5758 1.5975 1.6206 1.6415 1.6632 1.6844 1.7043 1.7269 1.7461 1.4099 1.4121 1.4217 1.4336 1.4571 1.4806 1.5035 1.5262 1.5487 1.5710 1.5931 1.6151 1.6366 1.6581 1.6795 1.7007 1.7218 1.3319 1.3340 1.3441 1.3562 1.3794 1.4018 D

pint (MPa) 420.3 419.9 418.7 417.4 414.2 411.1 407.9 404.5 401.0 397.6 394.2 390.4 386.7 382.9 379.1 375.2 371.3 420.6 420.2 419.2 417.8 414.6 411.6 408.3 405.1 401.6 398.3 394.6 391.2 387.6 383.9 380.5 376.4 372.9 420.3 420.0 418.9 417.4 414.5 411.4 408.3 405.1 401.8 398.4 395.0 391.5 388.0 384.4 380.7 377.1 373.4 417.0 416.7 415.6 414.3 411.6 409.0

cp cv (J·kg−1·K−1) (J·kg−1·K−1) 1470.93 1470.87 1470.49 1470.16 1469.55 1469.21 1469.02 1468.93 1469.00 1469.16 1469.43 1469.80 1470.25 1470.77 1471.37 1472.03 1472.75 1489.92 1489.89 1489.67 1489.30 1488.82 1488.55 1488.42 1488.37 1488.47 1488.60 1488.89 1489.13 1489.50 1489.86 1490.26 1490.75 1491.18 1499.35 1499.29 1499.08 1498.83 1498.49 1498.25 1498.23 1498.27 1498.37 1498.59 1498.85 1499.12 1499.51 1499.88 1500.28 1500.72 1501.12 1527.42 1527.50 1527.44 1527.33 1527.40 1527.59

1269.89 1270.04 1270.44 1270.93 1272.06 1273.17 1274.37 1275.52 1276.76 1277.93 1279.11 1280.39 1281.64 1282.89 1284.16 1285.42 1286.70 1287.50 1287.84 1288.32 1288.94 1290.51 1291.90 1293.39 1294.72 1296.15 1297.42 1298.83 1299.99 1301.25 1302.41 1303.49 1304.70 1305.69 1296.62 1296.78 1297.49 1298.32 1299.98 1301.56 1303.16 1304.67 1306.11 1307.54 1308.88 1310.13 1311.41 1312.58 1313.71 1314.79 1315.78 1325.43 1325.77 1326.78 1327.85 1330.06 1332.09

u (m·s−1)

κs

1447.68 1450.37 1460.30 1471.16 1495.47 1517.31 1539.57 1560.93 1582.74 1602.50 1621.87 1642.52 1661.79 1680.46 1699.09 1717.30 1735.20 1427.37 1431.31 1439.22 1450.79 1476.09 1498.09 1521.20 1542.35 1564.39 1584.54 1605.94 1624.86 1644.45 1663.29 1680.80 1700.56 1717.08 1416.94 1419.23 1429.10 1441.26 1465.03 1488.37 1510.94 1532.88 1554.43 1575.52 1596.05 1616.25 1635.89 1655.16 1674.19 1692.79 1711.08 1384.85 1387.30 1398.20 1410.97 1435.43 1458.59

27180.45 2250.359 524.529 287.353 145.179 101.739 78.662 65.076 55.617 49.330 44.560 40.524 37.456 34.968 32.854 31.070 29.537 26258.20 1533.640 542.769 282.979 140.048 98.596 75.928 63.176 54.054 47.965 42.988 39.490 36.507 34.114 32.206 30.347 28.988 25794.84 2556.006 528.438 270.552 140.668 97.011 75.270 62.270 53.543 47.286 42.616 38.968 36.045 33.659 31.654 29.961 28.509 24410.00 2256.368 469.655 247.367 131.502 92.384



Article

Table 4. continued p (MPa)

ρ (kg·m−3)

T (K)

κT (MPa−1)

αp (K−1)

40.009 49.994 60.130 70.102 79.871 90.021 99.922 109.826 121.633 129.825 139.153 0.101 1.557 5.234 9.847 19.578 29.996 39.827 49.998 59.777 69.992 79.293 89.992 98.041 109.813 119.774 129.813 138.881 0.101 1.725 5.397 10.408 20.124 29.996 40.316 49.992 60.245 69.993 79.196 89.993 97.743 109.795 119.409 129.794 139.089 0.101 1.630 4.913 10.553 20.238 29.993 40.245 49.994 59.359 69.993 78.937 89.993 99.354 109.823 118.844

1307.36 1312.48 1317.55 1322.42 1327.08 1331.79 1336.27 1340.63 1345.69 1349.10 1352.88 1270.06 1270.96 1273.19 1275.96 1281.68 1287.62 1293.05 1298.50 1303.59 1308.75 1313.31 1318.40 1322.14 1327.45 1331.81 1336.09 1339.86 1254.43 1255.50 1257.90 1261.13 1267.23 1273.21 1279.23 1284.69 1290.27 1295.39 1300.06 1305.36 1309.04 1314.57 1318.82 1323.26 1327.11 1239.44 1240.50 1242.76 1246.58 1252.94 1259.10 1265.34 1271.05 1276.34 1282.13 1286.82 1292.43 1297.01 1301.97 1306.11

313.15 313.15 313.16 313.15 313.15 313.15 313.15 313.15 313.15 313.15 313.15 333.15 333.09 333.10 333.11 333.14 333.15 333.17 333.16 333.16 333.15 333.15 333.15 333.15 333.15 333.16 333.16 333.16 353.15 353.14 353.13 353.14 353.19 353.17 353.16 353.15 353.14 353.14 353.14 353.15 353.15 353.15 353.14 353.15 353.16 373.15 373.14 373.14 373.16 373.15 373.15 373.14 373.15 373.15 373.14 373.12 373.14 373.14 373.14 373.15

398.7 384.8 371.8 359.8 348.9 338.3 328.6 319.5 309.3 302.7 295.5 501.1 497.6 489.1 478.9 458.8 439.2 422.3 406.2 392.0 378.2 366.5 354.1 345.2 333.2 323.7 314.6 306.9 537.9 533.4 523.3 510.4 487.1 465.7 445.3 427.9 410.9 396.1 383.1 369.0 359.5 345.8 335.6 325.3 316.7 579.4 574.2 563.5 546.1 518.6 493.8 470.3 450.1 432.3 413.8 399.5 383.3 370.5 357.3 346.7

568.1 557.1 546.7 537.3 528.6 520.2 512.5 505.3 497.3 492.1 486.5 614.3 611.8 605.6 598.1 583.5 569.3 557.1 545.7 535.6 526.0 517.9 509.3 503.3 495.2 488.8 482.9 477.9 604.9 601.8 595.0 586.2 570.5 556.4 543.2 532.1 521.6 512.5 504.7 496.4 491.0 483.3 477.8 472.3 467.9 601.3 597.9 590.9 579.5 562.1 546.7 532.5 520.6 510.5 500.4 492.8 484.5 478.2 472.0 467.3

γ (cp − cv) (J·kg−1·K−1) (MPa·K−1) 193.8 192.4 191.0 189.9 188.9 188.1 187.3 186.7 186.1 185.7 185.4 197.6 197.2 196.2 195.1 192.9 190.9 189.4 188.1 187.0 186.2 185.6 185.1 184.9 184.7 184.7 184.8 185.1 191.5 191.0 189.9 188.5 186.2 184.4 183.0 181.9 181.2 180.8 180.6 180.7 180.9 181.5 182.1 183.0 184.0 187.9 187.3 186.0 184.1 181.4 179.4 177.8 176.8 176.3 176.1 176.3 176.8 177.6 178.7 179.9

1.4248 1.4476 1.4706 1.4931 1.5150 1.5377 1.5598 1.5818 1.6079 1.6259 1.6465 1.2259 1.2296 1.2382 1.2490 1.2717 1.2961 1.3192 1.3432 1.3664 1.3907 1.4128 1.4384 1.4578 1.4862 1.5103 1.5348 1.5571 1.1245 1.1283 1.1369 1.1486 1.1713 1.1949 1.2199 1.2437 1.2693 1.2938 1.3173 1.3452 1.3656 1.3976 1.4236 1.4519 1.4776 1.0378 1.0412 1.0486 1.0613 1.0838 1.1071 1.1323 1.1568 1.1810 1.2092 1.2335 1.2641 1.2907 1.3211 1.3478 E

pint (MPa) 406.2 403.3 400.4 397.5 394.6 391.5 388.5 385.5 381.9 379.3 376.4 408.3 408.0 407.2 406.2 404.1 401.8 399.7 397.5 395.4 393.3 391.4 389.2 387.6 385.3 383.4 381.5 379.9 397.0 396.7 396.1 395.2 393.6 392.0 390.5 389.2 388.0 386.9 386.0 385.1 384.5 383.8 383.3 382.9 382.7 387.1 386.9 386.4 385.5 384.2 383.1 382.3 381.7 381.3 381.2 381.3 381.7 382.3 383.1 384.1

cp cv (J·kg−1·K−1) (J·kg−1·K−1) 1527.89 1528.27 1528.72 1529.17 1529.65 1530.15 1530.65 1531.13 1531.68 1532.04 1532.43 1564.53 1564.46 1564.61 1564.84 1565.45 1566.22 1567.06 1567.93 1568.82 1569.75 1570.61 1571.57 1572.27 1573.24 1574.02 1574.73 1575.30 1601.55 1601.55 1601.62 1601.82 1602.46 1603.19 1604.13 1605.12 1606.22 1607.32 1608.37 1609.59 1610.43 1611.68 1612.60 1613.55 1614.32 1638.34 1638.11 1637.69 1637.16 1636.56 1636.37 1636.47 1636.82 1637.30 1637.95 1638.56 1639.41 1640.13 1640.92 1641.60

1334.07 1335.92 1337.69 1339.27 1340.72 1342.10 1343.32 1344.43 1345.60 1346.31 1347.03 1366.94 1367.26 1368.40 1369.79 1372.59 1375.31 1377.69 1379.87 1381.79 1383.56 1385.01 1386.46 1387.40 1388.54 1389.33 1389.90 1390.26 1410.05 1410.57 1411.73 1413.30 1416.22 1418.77 1421.18 1423.18 1425.03 1426.55 1427.75 1428.91 1429.54 1430.21 1430.47 1430.54 1430.37 1450.46 1450.84 1451.66 1453.04 1455.14 1457.02 1458.68 1460.02 1461.04 1461.87 1462.31 1462.60 1462.55 1462.21 1461.67

u (m·s−1)

κs

1481.96 1504.67 1527.15 1548.80 1569.53 1590.62 1610.78 1630.57 1653.68 1669.38 1687.03 1341.16 1345.26 1355.12 1367.38 1392.67 1419.02 1443.19 1467.63 1490.55 1513.97 1534.82 1558.32 1575.68 1600.59 1621.25 1641.74 1659.95 1297.43 1302.17 1312.77 1326.99 1353.89 1380.56 1407.68 1432.47 1458.12 1481.94 1503.99 1529.33 1547.21 1574.52 1595.93 1618.66 1638.70 1254.20 1259.02 1269.25 1286.52 1315.55 1343.94 1372.98 1399.84 1425.09 1453.15 1476.28 1504.27 1527.56 1553.16 1574.88

71.791 59.459 51.120 45.265 40.941 37.438 34.703 32.458 30.256 28.960 27.670 22612.85 1476.956 446.629 242.252 126.968 86.439 67.624 55.943 48.452 42.860 39.017 35.576 33.481 30.968 29.225 27.740 26.582 20905.56 1234.081 401.670 213.371 115.428 80.900 62.875 52.729 45.532 40.641 37.128 33.921 32.056 29.680 28.129 26.713 25.625 19301.81 1206.289 407.502 195.520 107.157 75.833 59.277 49.825 43.672 38.684 35.531 32.499 30.462 28.599 27.258



Article

Table 4. continued p (MPa)

ρ (kg·m−3)

T (K)

κT (MPa−1)

αp (K−1)

129.824 139.225 0.101 1.385 5.168 10.362 20.141 29.997 39.789 49.984 60.109 69.997 79.320 89.992 99.285 109.795 118.691 129.796 139.693 0.101 1.691 5.006 10.288 19.961 29.916 39.957 49.993 59.956 69.993 80.334 89.994 99.873 109.886 119.193 129.886 139.479

1311.00 1315.08 1224.41 1225.37 1228.15 1231.90 1238.76 1245.39 1251.72 1258.04 1264.05 1269.67 1274.76 1280.34 1284.99 1290.04 1294.13 1299.01 1303.18 1209.39 1210.63 1213.19 1217.19 1224.32 1231.38 1238.21 1244.75 1250.96 1256.95 1262.84 1268.07 1273.17 1278.08 1282.42 1287.14 1291.12

373.15 373.15 393.15 393.17 393.18 393.14 393.12 393.13 393.13 393.15 393.16 393.15 393.16 393.15 393.14 393.15 393.14 393.15 393.15 413.15 413.13 413.15 413.20 413.20 413.20 413.20 413.20 413.21 413.18 413.15 413.15 413.13 413.15 413.18 413.17 413.17

334.6 325.0 629.4 624.1 608.9 589.2 555.6 525.6 499.1 474.3 452.0 432.4 415.4 397.5 383.3 368.4 356.7 343.1 331.9 696.0 687.4 670.3 645.0 603.2 565.8 532.6 503.3 477.3 453.8 431.9 413.4 396.1 380.0 366.3 351.7 339.5

462.1 458.2 614.7 611.1 601.0 588.1 566.6 548.0 532.2 517.9 505.7 495.4 486.8 478.4 471.9 465.6 461.0 456.0 452.1 662.6 656.4 644.1 626.1 597.2 572.3 551.1 533.2 518.1 505.1 493.7 484.6 476.6 469.6 464.1 458.7 454.6

γ (cp − cv) (J·kg−1·K−1) (MPa·K−1) 181.7 183.3 192.8 192.0 189.9 187.3 183.3 180.3 178.2 176.8 176.0 175.8 176.0 176.8 177.8 179.4 181.0 183.4 185.8 215.6 213.9 210.8 206.3 199.5 194.2 190.3 187.5 185.8 184.8 184.6 185.1 186.1 187.6 189.5 192.1 194.7

1.3810 1.4100 0.9766 0.9792 0.9870 0.9981 1.0198 1.0426 1.0664 1.0921 1.1187 1.1457 1.1721 1.2033 1.2313 1.2640 1.2924 1.3289 1.3623 0.9521 0.9549 0.9608 0.9707 0.9900 1.0115 1.0348 1.0595 1.0855 1.1132 1.1431 1.1721 1.2032 1.2358 1.2671 1.3044 1.3390

pint (MPa)

cp cv (J·kg−1·K−1) (J·kg−1·K−1)

385.5 386.9 383.8 383.6 382.9 382.0 380.8 379.9 379.4 379.4 379.7 380.5 381.5 383.1 384.8 387.1 389.4 392.7 395.9 393.2 392.8 392.0 390.8 389.1 388.1 387.6 387.8 388.6 389.9 391.9 394.3 397.2 400.7 404.4 409.1 413.7

1642.35 1642.95 1674.25 1673.59 1671.67 1669.23 1665.52 1662.64 1660.41 1658.63 1657.27 1656.25 1655.51 1654.86 1654.42 1654.04 1653.78 1653.50 1653.28 1710.42 1708.17 1703.83 1697.51 1687.42 1678.79 1671.52 1665.38 1660.18 1655.68 1651.68 1648.39 1645.42 1642.68 1640.34 1637.95 1635.96

u (m·s−1)

κs

1600.92 1622.91 1210.95 1215.31 1228.17 1245.65 1277.64 1308.87 1339.05 1369.65 1399.32 1427.64 1453.83 1483.26 1508.43 1536.43 1559.79 1588.54 1613.81 1166.12 1172.22 1184.67 1204.17 1239.07 1273.88 1307.97 1341.12 1373.22 1404.87 1436.81 1465.99 1495.38 1524.67 1551.51 1581.95 1608.92

25.882 24.879 17776.70 1306.753 358.485 184.496 100.418 71.137 56.415 47.217 41.176 36.966 33.963 31.295 29.444 27.732 26.525 25.255 24.300 16277.07 983.484 340.072 171.557 94.186 66.813 53.027 44.790 39.347 35.443 32.449 30.278 28.501 27.034 25.897 24.802 23.970

1460.71 1459.61 1481.50 1481.59 1481.77 1481.93 1482.19 1482.30 1482.20 1481.88 1481.30 1480.48 1479.49 1478.08 1476.60 1474.65 1472.77 1470.12 1467.49 1494.83 1494.24 1493.06 1491.19 1487.91 1484.59 1481.25 1477.86 1474.40 1470.85 1467.04 1463.30 1459.33 1455.04 1450.84 1445.89 1441.23

a

Standard uncertainty u are u(T) = 0.015 K, pressure - u(p) = 0.00025 MPa for p < 0.25 MPa, u(p) = 0.0025 MPa for p < 2.5 MPa, u(p) = 0.01 MPa for p < 10 MPa, u(p) = 0.1 MPa for p < 100 MPa, and u(p) = 0.25 MPa for p > 100 MPa and the combined expanded uncertainty Uc is Uc(ρ) = 0.3 kg·m−3 for 333.15 K < T < 413.15 K and p < 100 MPa, (ρ) = (0.3 to 0.8) kg·m−3 for 283.15 K < T < 413.15 K and p ≥ 100 MPa, 283.15 K < T < 333.15 K and p < 100 MPa, (0.95 level of confidence).

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It is necessary to know the measured ρHPM and corrected density ρ as a function of viscosity η(p,T). There are no existing studies noting the viscosity of [BMIM][TFO] under higher pressures. We measured the dynamic viscosity η(p0,T) of [BMIM][TFO] at ambient pressures and temperatures at T = (283.15 to 413.15) K using an SVM 3000 viscometer with an accuracy in Δη/η = ±0.35% and Rheometer MCR 302 in Δη/η = ±1%. Obtained values6 and reference results were used during the calculation of viscosity correction (ρHPM − ρ)/ ρHPM. Due to a lack of high pressure viscosity data for [BMIM][TFO], we could not precisely estimate the viscosity corrections at high pressures. Estimation of the sensitivity of the corrections on the viscosity changes due to pressure increases was already discussed in our previous publication.41 In this case, the uncertainty of the density measurements can be predicted up to Uc(ρ) = 0.3 kg·m−3 for 333.15 K < T < 413.15 K and p < 100 MPa, (ρ) = (0.3 to 0.8) kg·m−3 for 283.15 K < T < 413.15 K and p ≥ 100 MPa, 283.15 K < T < 333.15 K and p < 100 MPa, (0.95 level of confidence).

RESULTS AND DISCUSSION The experimental density values of [BMIM][TFO] are presented in Tables 3 and 4 and in Figure 1. Densities values ρ(p0,T) (kg·m−3) were described using the polynomial equation 2

ρ(p0 , T ) =

∑ diT i

(2)

0

where di are the coefficients of eq 2 and are presented in Table 5. Equation 2 describes the obtained densities at ambient pressure within APD in ±0.016%. Investigated density results at high state parameters as a function of temperature and pressure were fitted to the EOS42 p(ρ , T )/MPa = A(T ) ·(ρ /g·cm−3)2 + B(T ) ·(ρ /g·cm−3)8 + C(T ) ·(ρ /g·cm−3)12

(3)

where the coefficients of A(T), B(T), and C(T) are temperature dependent fitting parameters: F



Article

Obtained thermophysical properties are presented in Table 4 alongside (p,ρ,T) data of [BMIM][TFO] and are shown in Figures 3−6. From Figure 3, it is observed that with the increase of pressure, isothermal compressibility (κT (MPa−1)) decreases at a constant temperature. Generally, the isothermal compressibility is very low for liquids. When the liquid is compressed with high pressures, the density increases because of the attraction between molecules. This explains the decrease in compressibility with increasing pressure. The plot can be interpreted as hyperbolic at high temperatures, whereas at low temperatures it is near linear. From Figure 4 it can be seen that the thermal coefficient of pressure goes up with pressure increasing (T = const) and goes down with temperature increasing (p = const). Figure 5 show us approximately constant values of isobaric heat capacity with increasing pressure at small temperatures (up to T = 313.16 K). Beyond this temperature, heat capacity increases with increasing pressure, except for the last two isotherms T = (393.15 and 413.17) K. In these temperatures, isobaric heat capacity decreases with increasing pressure, and characteristics differ from other isotherms. Such behavior can be explained by the density uncertainties up to Δρ/ρ = ±0.8 kg·m−3. The speed of sound values increase with pressure increasing in all temperatures and decrease with temperature increasing (Figure 6).

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DISCUSSION AND LITERATURE COMPARISON The experimental values were compared with the literature values. Figure S2 presents the plot of percent deviation of experimental ρexp. and literature ρlit. densities of [BMIM][TFO] at p = 0.101 MPa. Figure S3 include the deviation of experimental ρexp. densities of [BMIM][TFO] from literature ρlit. densities (a) at various temperatures versus pressure p and (b) at various pressures versus temperatures T. After fitting of EOS, the obtained experimental values and calculated thermophysical properties [BMIM][TFO] were compared with available literature values (Table 1). First, the ambient pressure literature density values (ρ(p0,T)) were compared. The first density values of [BMIM][TFO] were obtained by Fredlake et al.7 The average percent deviation (APD) of five compared density values7 is Δρ/ρ = ±0.34%. These literature values are higher than present values. The maximum percent deviation (MPD) obtained was Δρ/ρ = 0.59% at T = 342.65 K. The large deviation between the two works as well as this deviation can be explained by the measurement method, which was carried out using the 1 mL pycnometers from Thomas Scientific.

Figure 1. Plot of pressure p of [BMIM][TFO] versus density ρ: (black diamond), 283.15 K; (black square), 293.16 K; (black triangle), 298.15 K; (black down-pointing triangle), 313.16 K; (black star), 333.14 K; (diamond), 353.15 K; (square), 373.14 K; (triangle), 393.15 K; (down-pointing triangle), 413.17 K; − calculated by eqs 3 and 4. 4

A (T ) =

3

3

∑ aiT i B(T ) = ∑ biT i C(T ) = ∑ ciT i i=1

i=0

i=0

(4)

The coefficients ai, bi, and ci are presented in Table 6. Figure 2 displays the plotted deviations of experimental density ρexp. of [BMIM][TFO] calculated by eqs 3 and 4 and density ρcal versus pressure p at T = (283.15 to 413.15) K. Equations 3 and 4 describe the density of [BMIM][TFO] with mean relative deviation Δρ/ρ = ±0.011% and maximal absolute deviation in Δρ = 0.36 kg m−3. Various thermophysical properties were calculated from EOS (eqs 3 and 4) using the fundamental equations (eqs 4−15)4 of thermodynamics. Table 5. Coefficients di of eq 2 d0 (kg·m−3) a

1562.6212321327

d1 (kg·m−3·K−1)

d2 (kg·m−3·K−2)

r

−0.976477371736507

0.29533388691716 × 10−3

0.999999

AAD = (100/n)·(ρexp-ρcal)/ρexp = ±0.016%.

a

Table 6. Values of the Coefficients ai, bi, and ci in eqs 3 and 4 a1 (m5·kg−1·s−2·K−1) −4.2692592829 b0 (m23·kg−7·s−2)

a

174.75249205667 c0 (m35·kg−11·s−2) −51.47152141

a2 (m5·kg−1·s−2·K−2)

a3 (m5·kg−1·s−2·K−3) −4

−0.4855 × 10 b2 (m23·kg−7·s−2·K−2)

0.0223841473231 b1 (m23·kg−7·s−2·K−1)

0.639493046 × 10−2 c2 (m35·kg−11·s−2·K−2)

−1.58386392 c1 (m ·kg−11·s−2·K−1) 35

−0.2041972953 × 10−2

0.55474275855

a4 (m5·kg−1·s−2·K−4) 0.419914 × 10−7 b3 (m23·kg−7·s−2·K−3) −0.816448 × 10−5 c3 (m35·kg−11·s−2·K−3) 0.248726540525 × 10−5

APD = (100/n)·(ρexp. − ρcal)/ρexp. = ±0.011%.

a

G



Article

Figure 2. Plot of deviations of experimental density ρexp. of [BMIM][TFO] calculated by eqs 3 and 4 and density ρcal versus pressure p at T = (283.15 to 413.15) K: (black diamond), 283.15 K; (black square), 293.16 K; (black triangle), 298.15 K; (black downpointing triangle), 313.16 K; (black star), 333.14 K; (diamond), 353.15 K; (square), 373.14 K; (triangle), 393.15 K; (down-pointing triangle), 413.17 K.

Figure 3. Plot of isothermal compressibility κT × 106 (MPa−1) of [BMIM][TFO] versus pressure p: (black diamond), 283.15 K; (black square), 293.16 K; (black triangle), 298.15 K; (black down-pointing triangle), 313.16 K; (black star), 333.14 K; (diamond), 353.15 K; (square), 373.14 K; (triangle), 393.15 K; (down-pointing triangle), 413.17 K; − best fit lines.

The next seven density values measured by Tokuda et al.8,9 were compared with present results: the first literature value from 2004 has Δρ/ρ = 0.29% deviation, but another six values from 2006 have Δρ/ρ = ± 0.019% APD. The MPD of results in ref 8 was obtained as Δρ/ρ = 0.02% at T = 298.15 K. APD of 11 experimental density values published by Gardas et al.10 is approximately Δρ/ρ = ±0.09%. This literature work has big deviation at low temperatures (up to Δρ/ρ = 0.33%), and deviation decreases with increasing temperature. The APD of ́ six experimental density values measured by Garcia-Miaja et al.11 from present values is approximately Δρ/ρ = ±0.006%. The seven density values of Ge et al.12 have Δρ/ρ = ±0.482% APD, with the Δρ/ρ = 0.644% maximum difference at T = 343.15 K. Jacquemin et al.13 provided eight density results, which were compared with present results and obtained Δρ/ρ = ± 0.015% APD. The MPD was Δρ/ρ = −0.034% at T = 293.15 K, and deviation decreased with increasing temperature. The 17 results of Soriano et al.16 have Δρ/ρ = ±0.5058% APD from this study, and they are higher. The deviation increases with increasing temperature and is maximum at T = 353.20 K as Δρ/ρ = 0.58%. The four experimental values studied by Tariq et al.17 have Δρ/ρ = ±0.148% APD from measurements in this work. The MPD is Δρ/ρ = 0.162% at T = 333.15 K. The 13 density values of Klomfar et al.19 measured using Merck products have Δρ/ρ = ±0.093% APD from this work. The MPD is Δρ/ρ = 0.13% at T = 303.10 K. Another 11 values of Klomfar et al.19 measured using a Sigma-Aldrich product have Δρ/ρ = ±0.054% APD

from our values with APD in Δρ/ρ = ±0.1%, and MPD at T = 337.95 K as Δρ/ρ = −0.115%. The nine density values determined by Shamsipur et al.20 have a Δρ/ρ = ±0.55% APD. The maximum uncertainty is Δρ/ρ = 0.61% at T = 293.15 K. Such high deviation can be explained by the use of the SVM 3000 viscometer, which can also produce density, but in Δρ/ρ = ±0.1% uncertainty. Also, IL was prepared in laboratory conditions. The seven experimental values measured by Zech et al.21 have a Δρ/ρ = ±0.03% APD from these results, and they are mostly smaller. The MPD is Δρ/ρ = ±0.05% at T = 278.15 K. One experimental value of Vercher et al.22 at T = 298.15 K has a Δρ/ρ = −0.024% deviation. The comparison of three density results of Gonzalez et al.23 with our results showed a Δρ/ρ = ±0.139% APD, and they are higher than present values. The 11 values of Seoane et al.25 compared to these results produce Δρ/ρ = ±0.148% and a slowly stable deviation obtained between both results. The six density values of Vercher et al.26 were compared with these work, and Δρ/ρ = ± 0.075% APD was received. The values in this literature source are lower than our values. The three density values of Gonzalez et al.27 were compared with present results, and Δρ/ρ = ±0.152% APD was received. The comparison of four density results of Batista et al.28 with results in this work gave us a Δρ/ρ = ±0.168% APD, and they are higher, with a maximum Δρ/ρ = 0.174% deviation at T = 298.15 K. Another six experimental values of Tsamba et al.29 have a Δρ/ρ = ±0.218% APD, and they are smaller than this work, with an MPD of Δρ/ρ = −0.245% at T = 297.98 K. The six H



Article

Figure 5. Plot of isobaric heat capacity cp (J·kg−1·K−1) of [BMIM][TFO] versus pressure p: (black diamond), 283.15 K; (black square), 293.16 K; (black triangle), 298.15 K; (black downpointing triangle), 313.16 K; (black star), 333.14 K; (diamond), 353.15 K; (square), 373.14 K; (triangle), 393.15 K; (down-pointing triangle), 413.17 K; − are best fit lines.

Figure 4. Plot of thermal coefficient of pressure γ (MPa·K−1) of [BMIM][TFO] versus pressure p: (black diamond), 283.15 K; (black square), 293.16 K; (black triangle), 298.15 K; (black down-pointing triangle), 313.16 K; (black star), 333.14 K; (diamond), 353.15 K; (square), 373.14 K; (triangle), 393.15 K; (down-pointing triangle), 413.17 K; − are best fit lines.

experimental density values of Montalbán et al.30 have a Δρ/ρ = ± 0.4% APD and are lower than present results. The one density value of Andanson et al.31 has a Δρ/ρ = 0.02% deviation at T = 298.15 K. The six density values of Anwar and Riyazuddeen32 showed good APD with values of this work in Δρ/ρ = ± 0.026%. The last three literature density values of [BMIM][TFO] at ambient pressure investigated by Khan et al.33 showed Δρ/ρ = ±0.744% APD with present values. The MPD is Δρ/ρ = 0.893% at T = 303.15 K. Such big deviation between can be explained as the results of measuring installation DSA 4500 (uncertainty is Δρ/ρ = ±0.1%). After comparing the literature density values at ambient pressure with results obtained in this work, it can be concluded that the literature values9,11,13,21,22,31,32 are close deviations of one another. These resources can be used as a reference density for [BMIM][TFO] at ambient pressure and at a wide range of temperatures T = (283.15 to 413.15) K. For comparison, 77 (p,ρ,T) data of Gardas et al.12 have a Δρ/ρ = ±0.103% APD with presented high pressure density values in this work. The MPD is Δρ/ρ = ± 0.337% at T = 293.15 K and p = 0.101 MPa. These values are mostly higher, and most values with high deviation are located between temperatures T = 293.15 and 313.15 K. The other 61 (p,ρ,T) data of Klomfar et al.24 have a Δρ/ρ = ±0.038% APD to present results, and MPD is Δρ/ρ = ±0.092% at T = 290.527 K and p = 10.565 MPa. These literature values are mostly higher. Most values with higher positive deviation are located

within the temperature interval T = (290.527 to 299.030) K, and those with a higher negative deviation are located within T = (323.398 to 350.144) K. The calculated isobaric heat capacity (cp) values at ambient pressure and various temperatures, presented in Table 1, were compared with the available literature results.5,7,11,43−49 The number of compared values from the past literature, temperature intervals of comparison, and average and maximum percent deviations are presented in Table 7. Figure S4 presents the plot of deviation of experimental cp,exp. and literature cp,lit. heat capacities of [BMIM][TFO] at p = 0.101 MPa versus temperature. The calculated speed of sound (u) values at ambient pressure and various temperatures, presented in Table 1, were compared with the available literature results.5,11,23,25,26 The number of compared values from the past literature, temperature intervals of comparison, and average and maximum percent deviations are presented in Table 8. There are no isochoric heat capacity (cv) values for [BMIM][TFO] present in the literature, and so comparisons were not possible.

■

CONCLUSIONS The (p,ρ,T) results of [BMIM][TFO] were reported. The measured results of [BMIM][TFO] were correlated using an EOS developed by our group, which fit well with deviations from experimental data within Δρ/ρ = ±0.011%. All available density (ρ) values of [BMIM][TFO] present in the literature were compared with our results. A good agreement was obtained at the result of comparison. The experimental (p,ρ,T) I



Article

results were used to derive various thermophysical properties at pressures p up to 140 MPa and at T = (283.15 to 413.15) K. For this purpose, the combination of experimental values of density and isobaric heat capacity at ambient pressure was used.

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ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.jced.8b00837. Chemical structure of [BMIM][TFO] and plots of deviation of experimental ρexp. and literature (PDF)

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AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. Tel: +49 381 498 9415. Fax: +49 381 4989402. Notes

The authors declare no competing financial interest.

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ACKNOWLEDGMENTS The support of these research studies from Rostock University and Azerbaijan Technical University is gratefully acknowledged.

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−1

REFERENCES

(1) Handy, S. Applications of ionic liquids in science and technology; InTechOpen: London, 2011. (2) Kokorin, A. Ionic Liquids: Theory, Properties, New Approaches; InTechOpen: London, 2011. (3) Shiflett, M.B.; Scurto, A.M. Ionic liquids: Current State and Future Directions; American Chemical Society: Washington, D.C., 2018.

Figure 6. Plot of speed of sound u (m·s ) of [BMIM][TFO] versus pressure p: (black diamond), 283.15 K; (black square), 293.16 K; (black triangle), 298.15 K; (black down-pointing triangle), 313.16 K; (black star), 333.14 K; (diamond), 353.15 K; (square), 373.14 K; (triangle), 393.15 K; (down-pointing triangle), 413.17 K; − are best fit lines.

Table 7. Comparison of Calculated Isobaric Heat Capacity cp Values at Ambient Pressure and Various Temperatures Presented in Table 1 with the Available Literature Values maximum percent deviation first author

number of compared values

Suleymanli5 Fredlake7 Diedrichs, DSC Q10043 Diedrichs, MDSCTM43 Diedrichs, Tian−Calvet43 11 ́ Garcia-Miaja 44 Ge Lin45 Yu46 Paulechka47 Paulechka48 Calvar49

9 2 23 18 23 6 14 14 12 39 10 31

temperature interval T of compared values (K) 283.15 298.10 313.15 328.15 313.16 293.15 293.00 293.20 303.20 292.86 290.98 323.15

to to to to to to to to to to to to

413.15 323.10 425.15 408.15 423.14 318.15 358.00 358.20 358.20 367.78 370.00 353.15

(cp,lit. − cp,cal)/cp,lit. (%)

T (K)


±0.022 ±4.470 ±1.170 ±1.775 ±0.455 ±1.860 ±6.190 ±1.300 ±1.270 ±1.050 ±1.040 ±3.460

373.15 323.10 313.15 408.15 313.16 303.15 358.00 293.20 303.20 320.27 320.00 353.15

0.052 5.340 1.689 2.831 1.708 1.931 7.881 1.766 2.027 1.155 1.099 4.407

Table 8. Comparison of Calculated Speed of Sound u Values at Ambient Pressure and Various Temperatures Presented in Table 1 with the Available Literature Values maximum percent deviation first author

number of compared values

Suleymanli5 11 ́ Garcia-Miaja

9 6 3 11 6

Gonzalez23 Seoane25 Vercher26

temperature interval T of compared values (K) 283.15 293.15 288.15 293.15 288.15

to to to to to

413.15 318.15 323.15 343.15 338.15 J


T (K)


±0.022 ±0.058 ±0.012 ±0.017 ±0.148

373.15 318.15 323.15 338.15 338.15

0.052 0.081 0.024 0.051 0.204



Article

pyrrolidinium bis(trifluoromethylsulfonyl)imide. J. Mol. Liq. 2010, 157, 43−50. (21) Zech, O.; Stoppa, A.; Buchner, R.; Kunz, W. The Conductivity of Imidazolium-Based Ionic Liquids from (248 to 468) K. B. Variation of the Anion. J. Chem. Eng. Data 2010, 55, 1774−1778. (22) Vercher, E.; Llopis, F. J.; González-Alfaro, V.; Miguel, P. J.; Martínez-Andreu, A. Refractive Indices and Deviations in Refractive Indices of Trifluoromethanesulfonate-Based Ionic Liquids in Water. J. Chem. Eng. Data 2011, 56, 4499−4504. (23) González, E. J.; Domínguez, Á .; Macedo, E. A. Physical and Excess Properties of Eight Binary Mixtures Containing Water and Ionic Liquids. J. Chem. Eng. Data 2012, 57, 2165−2176. (24) Klomfar, J.; Součková, M.; Pátek, J. P−ρ−TMeasurements for 1-Alkyl-3-methylimidazolium-Based Ionic Liquids with Tetrafluoroborate and a Trifluoromethanesulfonate Anion. J. Chem. Eng. Data 2012, 57, 708−720. (25) Seoane, R. G.; Corderí, S.; Gómez, E.; Calvar, N.; González, E. J.; Macedo, E. A.; Domínguez, A. Temperature Dependence and Structural Influence on the Thermophysical Properties of Eleven Commercial Ionic Liquids. Ind. Eng. Chem. Res. 2012, 51, 2492−2504. (26) Vercher, E.; Miguel, P. J.; Llopis, F. J.; Orchillés, A. V.; Martínez-Andreu, A. Volumetric and Acoustic Properties of Aqueous Solutions of Trifluoromethanesulfonate-Based Ionic Liquids at Several Temperatures. J. Chem. Eng. Data 2012, 57, 1953−1963. (27) González, E. J.; Calvar, N.; Domínguez, A.; Macedo, E. A. Osmotic and apparent molar properties of binary mixtures alcohol + 1-butyl-3-methylimidazolium trifluoromethanesulfonate ionic liquid. J. Chem. Thermodyn. 2013, 61, 64−73. (28) Batista, M. L. S.; Tomé, L. I. N.; Neves, C. M. S. S.; Gomes, J. R. B.; Coutinho, J. A. P. Characterization of systems of thiophene and benzene with ionic liquids. J. Mol. Liq. 2014, 192, 26−31. (29) Mbondo Tsamba, B. E.; Sarraute, S.; Traïkia, M.; Husson, P. Transport Properties and Ionic Association in Pure ImidazoliumBased Ionic Liquids as a Function of Temperature. J. Chem. Eng. Data 2014, 59, 1747−1754. (30) Montalbán, M. G.; Bolívar, C. L.; Guillermo Díaz Baños, F.; Víllora, G. Effect of Temperature, Anion, and Alkyl Chain Length on the Density and Refractive Index of 1-Alkyl-3-methylimidazoliumBased Ionic Liquids. J. Chem. Eng. Data 2015, 60, 1986−1996. (31) Andanson, J.-M.; Meng, X.; Traïkia, M.; Husson, P. Quantification of the impact of water as an impurity on standard physico-chemical properties of ionic liquids. J. Chem. Thermodyn. 2016, 94, 169−176. (32) Anwar, N.; Riyazuddeen. Interaction of 1-Butyl-3-methylimidazolium Trifluoromethanesulfonate with Ethyl Acetate/1-Butanol: Thermophysical Properties. J. Solution Chem. 2016, 45, 1077−1094. (33) Khan, S. N.; Hailegiorgis, S. M.; Man, Z.; Shariff, A. M.; Garg, S. Thermophysical properties of concentrated aqueous solution of Nmethyldiethanolamine (MDEA), piperazine (PZ), and ionic liquids hybrid solvent for CO2 capture. J. Mol. Liq. 2017, 229, 221−229. (34) Safarov, J.; Millero, F.; Feistel, R.; Heintz, A.; Hassel, E. Thermodynamic properties of standard seawater: extensions to high temperatures and pressures. Ocean Sci. 2009, 5, 235−246. (35) Nabiyev, N. D.; Bashirov, M. M.; Safarov, J. T.; Shahverdiyev, A. N.; Hassel, E. P. Thermodynamic Properties of the Geothermal Resources (Khachmaz and Sabir-oba) of Azerbaijan. J. Chem. Eng. Data 2009, 54, 1799−1806. (36) Harris, K. R.; Kanakubo, M. Self-Diffusion Coefficients and Related Transport Properties for a Number of Fragile Ionic Liquids. J. Chem. Eng. Data 2016, 61, 2399−2411. (37) Harris, K. R.; Kanakubo, M.; Woolf, L. A. Temperature and Pressure Dependence of the Viscosity of the Ionic Liquids 1-Methyl3-octylimidazolium Hexafluorophosphate and 1-Methyl-3-octylimidazolium Tetrafluoroborate. J. Chem. Eng. Data 2006, 51, 1161−1167. (38) Stabinger, H. Density Measurement using Modern Oscillating Transducers; South Yorkshire Trading Standards Unit, Sheffield, 1994. (39) Aschcroft, S. J.; Booker, D. R.; Turner, J. C. R. Density measurements by oscillating tube. J. Chem. Soc., Faraday Trans. 1990, 86, 145−149.

(4) Safarov, J.; Hamidova, R.; Zepik, S.; Schmidt, H.; Kul, I.; Shahverdiyev, A.; Hassel, E. Thermophysical Properties of 1-hexyl-3methylimidazolium bis(trifluoromethylsulfonyl) imide at high temperatures and pressures. J. Mol. Liq. 2013, 187, 137−156. (5) Suleymanli, Kh.; Uysal, D.; Hamidova, R.; Aliyev, A.; Safarov, J.; Shahverdiyev, A.; Hassel, E. Heat capacity and speed of sound of some ionic liquids over wide range of temperature. Transactions of Azerbaijan National Academy of Sciences, Series of Physical-mathematical and Technical Sciences 2017, 37, 110−115. (6) Safarov, J.; Guluzade, A.; Hamidova, R.; Hassel, E. Study of viscosity of 1-butyl-3-methylimidazolium trifluoromethanesulfonate in a wide range of temperatures and ambient pressure. Journal of Scientific Works of Azerbaijan Technical University 2018, 2, 65−74. (7) Fredlake, C. P.; Crosthwaite, J. M.; Hert, D. G.; Aki, S. N. V. K.; Brennecke, J. F. Thermophysical Properties of Imidazolium-Based Ionic Liquids. J. Chem. Eng. Data 2004, 49, 954−964. (8) Tokuda, H.; Hayamizu, K.; Ishii, K.; Susan, M. A. B. H.; Watanabe, M. Physicochemical Properties and Structures of Room Temperature Ionic Liquids. 1. Variation of Anionic Species. J. Phys. Chem. B 2004, 108, 16593−16600. (9) Tokuda, H.; Tsuzuki, S.; Susan, Md. A. B. H.; Hayamizu, K.; Watanabe, M. How Ionic Are Room-Temperature Ionic Liquids? An Indicator of the Physicochemical Properties. J. Phys. Chem. B 2006, 110, 19593−19600. (10) Gardas, R. L.; Freire, M. G.; Carvalho, P. J.; Marrucho, I. M.; Fonseca, I. M. A.; Ferreira, A. G. M.; Coutinho, J. A. P. High-Pressure Densities and Derived Thermodynamic Properties of ImidazoliumBased Ionic Liquids. J. Chem. Eng. Data 2007, 52, 80−88. (11) García-Miaja, G.; Troncoso, J.; Romaní, L. Excess properties for binary systems ionic liquid + ethanol: Experimental results and theoretical description using the ERAS model. Fluid Phase Equilib. 2008, 274, 59−67. (12) Ge, M.-L.; Zhao, R.-S.; Yi, Y.-F.; Zhang, Q.; Wang, L.-S. Densities and Viscosities of 1-Butyl-3-methylimidazolium Trifluoromethanesulfonate + H2O Binary Mixtures at T= (303.15 to 343.15) K. J. Chem. Eng. Data 2008, 53, 2408−2411. (13) Jacquemin, J.; Ge, R.; Nancarrow, P.; Rooney, D. W.; Costa Gomes, M. F.; Pádua, A. A. H.; Hardacre, C. Prediction of Ionic Liquid Properties. I. Volumetric Properties as a Function of Temperature at 0.1 MPa. J. Chem. Eng. Data 2008, 53, 716−726. (14) McHale, G.; Hardacre, C.; Ge, R.; Doy, N.; Allen, R. W. K.; MacInnes, J. M.; Bown, M. R.; Newton, M. I. Density-Viscosity Product of Small-Volume Ionic Liquid Samples Using Quartz Crystal Impedance Analysis. Anal. Chem. 2008, 80, 5806−5811. (15) García-Miaja, G.; Troncoso, J.; Romaní, L. Excess enthalpy, density, and heat capacity for binary systems of alkylimidazoliumbased ionic liquids + water. J. Chem. Thermodyn. 2009, 41, 161−166. (16) Soriano, A. N.; Jr. Doma, B. T.; Li, M.-H. Measurements of the density and refractive index for 1-n-butyl-3-methylimidazolium-based ionic liquids. J. Chem. Thermodyn. 2009, 41, 301−307. (17) Tariq, M.; Forte, P. A. S.; Costa Gomes, M. F.; Canongia Lopes, J. N.; Rebelo, L. P. N. Densities and refractive indices of imidazolium- and phosphonium-based ionic liquids: Effect of temperature, alkyl chain length, and anion. J. Chem. Thermodyn. 2009, 41, 790−798. (18) Tsuzuki, S.; Shinoda, W.; Saito, H.; Mikami, M.; Tokuda, H.; Watanabe, M. Molecular Dynamics Simulations of Ionic Liquids: Cation and Anion Dependence of Self-Diffusion Coefficients of Ions. J. Phys. Chem. B 2009, 113, 10641−10649. (19) Klomfar, J.; Součková, M.; Pátek, J. Temperature Dependence Measurements of the Density at 0.1 MPa for 1-Alkyl-3-methylimidazolium-Based Ionic Liquids with the Trifluoromethanesulfonate and Tetrafluoroborate Anion. J. Chem. Eng. Data 2010, 55, 4054− 4057. (20) Shamsipur, M.; Beigi, A. A. M.; Teymouri, M.; Pourmortazavi, S. M.; Irandoust, M. Physical and electrochemical properties of ionic liquids 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3methylimidazolium trifluoromethanesulfonate and 1-butyl-1-methylK



Article

(40) Segovia, J. J.; Fandiño, O.; López, E. R.; Lugo, L.; Martín, M. C.; Fernández, J. Automated densimetric system: Measurements and uncertainties for compressed fluids. J. Chem. Thermodyn. 2009, 41, 632−638. (41) Safarov, J.; Lesch, F.; Suleymanli, K.; Aliyev, A.; Shahverdiyev, A.; Hassel, E.; Abdulagatov, I. High-temperature and high-pressure density measurements and other derived thermodynamic properties of 1-butyl-3-methylimidazolium tris (pentafluoroethyl) trifluorophosphate. Thermochim. Acta 2017, 658, 14−23. (42) Safarov, J. T. The investigation of the (p,ρ,T) and (ps,ρs,Ts) properties of {(1-x) CH3OH + xLiBr} for the application in absorption refrigeration machines and heat pumps. J. Chem. Thermodyn. 2003, 35, 1929−1937. (43) Diedrichs, A.; Gmehling, J. Measurement of heat capacities of ionic liquids by differential scanning calorimetry. Fluid Phase Equilib. 2006, 244, 68−77. (44) Ge, R.; Hardacre, C; Jacquemin, J.; Nancarrow, P.; Rooney, D. W. Heat Capacities of Ionic Liquids as a Function of Temperature at 0.1 MPa. Measurement and Prediction. J. Chem. Eng. Data 2008, 53, 2148−2153. (45) Lin, P.-Y.; Soriano, A. N.; Caparanga, A. R.; Li, M.-H. Molar heat capacity and electrolytic conductivity of aqueous solutions of [Bmim][MeSO4] and [Bmim][triflate]. Thermochim. Acta 2009, 496, 105−109. (46) Yu, Y.-H.; Soriano, A. N.; Li, M.-H. Heat capacities and electrical conductivities of 1-n-butyl-3-methylimidazolium-based ionic liquids. Thermochim. Acta 2009, 482, 42−48. (47) Paulechka, Y. U.; Kabo, A. G.; Blokhin, A. V.; Kabo, G. J.; Shevelyova, M. P. Heat Capacity of Ionic Liquids: Experimental Determination and Correlations with Molar Volume. J. Chem. Eng. Data 2010, 55, 2719−2724. (48) Paulechka, Y. U.; Kohut, S. V.; Blokhin, A. V.; Kabo, G. J. Thermodynamic properties of 1-butyl-3-methylimidazolium trifluoromethanesulfonate ionic liquid in the condensed state. Thermochim. Acta 2010, 511, 119−123. (49) Calvar, N.; Gómez, E.; Macedo, E. A.; Domínguez, Á . Thermal analysis and heat capacities of pyridinium and imidazolium ionic liquids. Thermochim. Acta 2013, 565, 178−82.

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Thermophysical Properties of 1-Butyl-3-methylimidazolium

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