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Allan N Soriano - One of the best experts on this subject based on the ideXlab platform.
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measurements and correlations of electrolytic conductivity and Molar Heat Capacity for the aqueous ionic liquid systems containing emim etso4 or emim cf3so3
Experimental Thermal and Fluid Science, 2011Co-Authors: Allan N Soriano, Rhoda B Leron, Menghui LiAbstract:Abstract New data on electrolytic conductivity, κ , and Molar Heat Capacity, C P , for aqueous solutions of ionic liquids, 1-ethyl-3-methylimidazolium ethylsulfate [Emim][EtSO 4 ] and 1-ethyl-3-methylimidazolium trifluoromethanesulfonate [Emim][CF 3 SO 3 ] obtained using a commercial conductivity meter and differential scanning calorimeter were reported here for temperature up to 353.2 K. The estimated measurement uncertainties for κ and C P were 1 and 2%, respectively. The present κ and C P data were reported as functions of temperature and composition. A modified empirical equation was used to correlate the temperature and composition dependence of the present κ data. An excess Molar Heat Capacity, C P E , expression using the Redlich–Kister type equation for the latter’s temperature and composition dependence was used to represent the measured C P and C P E of the considered solvent systems. The applied correlations represented the κ and C P measurements satisfactorily as indicated by an overall average deviation of 1.9 and 0.1%, respectively.
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Molar Heat Capacity of four aqueous ionic liquid mixtures
Thermochimica Acta, 2011Co-Authors: Allan N Soriano, Rhoda B LeronAbstract:Abstract As a continuation of our systematic study on physicochemical characterization of aqueous solution of ionic liquids, new measurements of Molar Heat Capacity for aqueous solutions of four ionic liquids were reported. The investigated ionic liquids were 1-butyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium bromide, 1-butyl-2,3-dimethylimidazolium tetrafluoroborate, and 1-butyl-2,3-dimethylimidazolium hexafluorophosphate. The Molar Heat capacities were measured at standard pressure and over the temperature range (303.2–353.2) K using a differential scanning calorimeter (DSC) having an estimated experimental uncertainty of about ±2% with liquid water as reference. The measured Molar Heat capacities were reported as function of temperature and composition and the excess Molar Heat capacities were calculated using a Redlich–Kister type equation. For the studied ionic liquids, results showed variations in the dependence of the excess Molar Heat capacities on temperature and composition. The applied correlation satisfactorily represented the Molar Heat Capacity measurements as shown by an acceptable overall average deviation of 0.09%.
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electrolytic conductivity and Molar Heat Capacity of two aqueous solutions of ionic liquids at room temperature measurements and correlations
The Journal of Chemical Thermodynamics, 2010Co-Authors: Allan N Soriano, Rhoda B Leron, Menghui LiAbstract:Abstract As part of our systematic study on physicochemical characterization of ionic liquids, in this work, we report new measurements of electrolytic conductivity and Molar Heat Capacity for aqueous solutions of two 1-ethyl-3-methylimidazolium-based ionic liquids, namely: 1-ethyl-3-methylimidazolium dicyanamide and 1-ethyl-3-methylimidazolium 2-(2-methoxyethoxy) ethylsulfate, at normal atmospheric condition and for temperatures up to 353.2 K. The electrolytic conductivity and Molar Heat Capacity were measured by a commercial conductivity meter and a differential scanning calorimeter (DSC), respectively. The estimated experimental uncertainties for the electrolytic conductivity and Molar Heat Capacity measurements were ±1% and ±2%, respectively. The property data are reported as functions of temperature and composition. A modified empirical equation from another researcher [1] was used to correlate the temperature and composition dependence of the our electrolytic conductivity results. An excess Molar Heat Capacity expression derived using a Redlich–Kister type equation was used to represent the temperature and composition dependence of the measured Molar Heat Capacity and calculated excess Molar Heat Capacity of the solvent systems considered. The correlations applied represent the our measurements satisfactorily as shown by an acceptable overall average deviation of 6.4% and 0.1%, respectively, for electrolytic conductivity and Molar Heat Capacity.
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a simple approach to predict Molar Heat Capacity of ionic liquids using group additivity method
Journal of The Taiwan Institute of Chemical Engineers, 2010Co-Authors: Allan N Soriano, Arjay M Agapito, Loui John Lee I Lagumbay, Alvin R CaparangaAbstract:Abstract In this work, we proposed a simple approach to predict Molar Heat Capacity of room-temperature ionic liquids by way of adding the contribution of the cations and anions to the property. The starting point was estimation of the contribution of the cation [Bmim+] to the Molar Heat Capacity at a particular temperature by way of semi-empirical quantum mechanical calculation of the fully optimized geometric structure of the reference cation using the PM3 package of HyperChem 8. From this computed Molar Heat Capacity contribution to the property of the ionic liquid, the Molar Heat Capacity of the other ionic liquids were predicted and compared with the values reported in the literature. The overall AAD for all the 3149 data points of the 32 considered ionic liquids was 0.69%, which is acceptable.
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Molar Heat Capacity and electrolytic conductivity of aqueous solutions of bmim meso4 and bmim triflate
Thermochimica Acta, 2009Co-Authors: Allan N Soriano, Alvin R Caparanga, Menghui LiAbstract:Abstract Here we report the new measurements of Molar Heat Capacity, CP and electrolytic conductivity, σ for aqueous solutions of 1-butyl-3-methylimidazolium methylsulfate, [Bmim][MeSO4] and 1-butyl-3-methylimidazolium trifluoromethanesulfonate, [Bmim][triflate]. Heat capacities were measured from 303.2 to 353.2 K with a differential scanning calorimeter. Electrolytic conductivities were measured from 293.2 to 353.2 K with a commercial conductivity meter. The estimated uncertainties of CP and σ measurements were ±2 and ±1%, respectively. The present measurements of CP and σ were presented as a function of temperature and composition. An excess Molar Heat Capacity C P E expression using the Redlich–Kister equation for the temperature and composition dependence was used to represent the measured CP and a modified empirical equation was used to correlate the temperature and composition dependence of the measured σ of the studied systems. The applied correlations represent the CP and σ measurements satisfactorily. The CP and σ values presented in this work are, in general, of sufficient accuracy for most engineering-design calculations.
Michael Grodzicki - One of the best experts on this subject based on the ideXlab platform.
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a low temperature calorimetric study of synthetic forsterite fayalite mg2sio4 fe2sio4 solid solutions an analysis of vibrational magnetic and electronic contributions to the Molar Heat Capacity and entropy of mixing
The Journal of Chemical Thermodynamics, 2007Co-Authors: Edgar Dachs, Charles A Geiger, Volker Von Seckendorff, Michael GrodzickiAbstract:Abstract The Molar Heat capacities (Cp,m) of a series of synthetic forsterite (Fo)–fayalite (Fa), (Mg2SiO4 + Fe2SiO4), olivines have been measured between 5 K and 300 K on milligram-sized samples with the Physical Properties Measurement System (Quantum Design®). Sharp, λ-type Heat Capacity anomalies are observed in the Fe-rich compositions fayalite, Fo10Fa90, Fo20Fa80, Fo30Fa70, and Fo40Fa60. The corresponding Neel temperatures TN decrease linearly from 64.5 K in fayalite to 32.8 K in Fo40Fa60 following the relationship TN = 79.02 · xFa − 14.07. Fo50Fa50 and Mg-richer olivines show weak broad features in the Heat Capacity data around 15 K to 20 K that decrease in magnitude with increasing forsterite content. In order to derive and separate Molar electronic, magnetic and vibrational Heat Capacity contributions, Cel,m, Cmag,m, and Cvib,m from the experimental Heat capacities (Ctot,m), we used a single-parametric phonon dispersion model to calculate Cvib,m for the solid-solution members and fayalite. The Cel,m + Cmag,m(= Ctot,m − Cvib,m) contributions were fit to expressions describing a Schottky-type electronic anomaly and a paramagnetic–antiferromagnetic transition. For Fo50Fa50 and Mg-richer olivines, our analysis of Ctot,m shows that also these compositions have a Cmag,m contribution with a maximum around 25 K. Decomposition of the Molar excess Heat Capacity C p ,m E into electronic, magnetic and vibrational contributions yields the largest absolute values for C mag,m E . Molar excess entropies of mixing S m E at T = 298.15 K were also calculated from the Heat Capacity data. Despite considerable C mag,m E , the Molar magnetic excess entropy at T = 298.15 K S mag,m E ( 298.15 K ) is only weakly negative for the solid solution (1.7 J · K−1 · mol−1to 2.7 J · K−1 · mol−1), because positive and negative contributions of C mag,m E / T as a function of temperature largely cancel each other between 0 K and 298.15 K. The Molar electronic excess Heat Capacity C el,m E is positive for all temperatures and compositions, S el,m E ( 298.15 K ) thus shows a positive contribution with a maximum of 0.8 J · K−1 · mol−1 for Fo50Fa50. The Molar vibrational excess entropy S vib,m E ( 298.15 K ) is also slightly positive for most members (maximum of 1.0 J · K−1 · mol−1 for Fo40Fa60). The resulting overall Molar excess entropy, S tot,m E ( 298.15 K ) = S vib,m E ( 298.15 K ) + S el,m E ( 298.15 K ) + S mag,m E ( 298.15 K ) along the (forsterite + fayalite) join is weakly negative within 2σ-uncertainty. Smoothed values of the Molar Heat Capacity Cp,m, the Molar entropies Δ 0 T S m , Molar enthalpies Δ 0 T H m , and the Molar Planck function Φm have been tabulated at selected temperatures for all olivine compositions.
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a low temperature calorimetric study of synthetic forsterite fayalite mg2sio4 fe2sio4 solid solutions an analysis of vibrational magnetic and electronic contributions to the Molar Heat Capacity and entropy of mixing
The Journal of Chemical Thermodynamics, 2007Co-Authors: Edgar Dachs, Charles A Geiger, Volker Von Seckendorff, Michael GrodzickiAbstract:The Molar Heat capacities (C-p,C-m)of a series of synthetic forsterite (Fo)-fayalite (Fa), (Mg2SiO4 + Fe2SiO4), olivines have been measured between 5 K and 300 K on milligram-sized samples with the Physical Properties Measurement System (Quantum Design ((R))). Sharp, k-type Heat Capacity anomalies are observed in the Fe-rich compositions fayalite, Fo(10)Fa(90), Fo(20)Fa(80), Fo(30)Fa(70), and Fo(40)Fa(60). The corresponding Neel temperatures T-N decrease linearly from 64.5 K in fayalite to 32.8 K in Fo(40)Fa(60) following the relationship T-N = 79.02 . x(Fa) - 14.07. Fo(50)Fa(50) and Mg-richer olivines show weak broad features in the Heat Capacity data around 15 K to 20 K that decrease in magnitude with increasing forsterite content. In order to derive and separate Molar electronic, magnetic and vibrational Heat Capacity contributions, C-el,C-m,C- C-mag,C-m,C- and C-vib,C-m from the experimental Heat capacities (C-tot,C-m), we used a single-parametric phonon dispersion model to calculate C-vib,C-m for the solid-solution members and fayalite. The C-el,C-m + C-mag,C-m(= C-tot,C-m - C-vib,C-m) contributions were fit to expressions describing a Schottky-type electronic anomaly and a paramagnetic-antiferromagnetic transition. For Fo(50)Fa(50) and Mg-richer olivines, our analysis of C-tot,C-m shows that also these compositions have a C-mag,C-m contribution with a maximum around 25 K. Decomposition of the Molar excess Heat Capacity C-p,m(E) into electronic, magnetic and vibrational contributions yields the largest absolute values for C-mag,m,(E). Molar excess entropies of mixingp S-m(E) C-mag,m,(E). Molar magnetic excess entropies of mixing S-m(E) at T = 298.15 K were also calculated from the Heat Capacity data. Despite Considerable the Molar magnetic excess entropy at T = 298.15 K S-mag,m(E) (298.15 K) is only weakly negative for the solid solution rnag,m mag,m of CE (1.7 J . K-1 mol(-1) to 2.7 J . K-1 . mol(-1)), because positive and negative contributions of C-el,m(E)/T as a function of temperature largely cancel each other between 0 K and 298.15 K. The Molar electronic excess Heat Capacity C-el,m(E) is positive for all temperatures and compositions, S-vib,m(E) (298.15 K) thus shows a positive contribution with a maximum of 0.8 J . K-1 mol(-1) for Fo(50)Fa(50). The Molar vibrational SE excess entropy S-vib,m(E) (298.15 K) is also slightly positive for most members (maximum of 1.0 J . K-1 . mol(-1) for Fo(40)Fa(60)). The resulting overall Molar excess entropy, S-tot,m(E) (298.15 K) = S-vib,m(E) (298.15 K) + S-el,m(E) (298.15 K) + S-mag.m(E) (298.15 K) along the (forsterite + fayalite) to Vi el magp TSttt, join is weakly negative within 2 sigma-uncertainty. Smoothed values of the Molar Heat Capacity C-p,C-m,C- the Molar entropies Delta(T)(0) S-m,S- Molar enthalpies A T H., and the Molar Planck function phi(m) have been tabulated at selected temperatures for all olivine compositions. (c) 2006 Elsevier Ltd. All rights reserved.
Rhoda B Leron - One of the best experts on this subject based on the ideXlab platform.
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Molar Heat Capacity of several aqueous solutions of n tris hydroxymethyl methyl 3 amino propanesulfonic acid taps glycol
Thermochimica Acta, 2012Co-Authors: Alvin R Caparanga, Rhoda B LeronAbstract:Abstract The Molar Heat Capacity ( C p ) of a potential solvent system for CO 2 absorption, containing water, glycol and n -[tris(hydroxymethyl)methyl-3-amino]propanesulfonic acid (TAPS), was measured at 30–80 °C and different concentrations via differential scanning calorimetry. Each of the glycols – diethylene glycol (DEG), triethylene glycol (TEG), tetraethylene glycol (T 4 EG), propylene glycol (PG), dipropylene glycol (DPG) and tripropylene glycol (TPG) – was mixed with TAPS + H 2 O to form ternary systems consisting of a fixed amount of the glycol (40 mass%) and variable TAPS/H 2 O proportions (4–16 mass% TAPS or 56–44% H 2 O). An extended Redlich–Kister -type equation was used to correlate Heat Capacity with concentration and temperature; the average absolute deviation (AAD) of the 198 data points from the corresponding values predicted by the correlation was 0.04%. The new set Heat Capacity data or the correlation, reported for the ternary system considered, can be used with high degree of accuracy in process design calculations for systems that will utilize these solvent systems.
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measurements and correlations of electrolytic conductivity and Molar Heat Capacity for the aqueous ionic liquid systems containing emim etso4 or emim cf3so3
Experimental Thermal and Fluid Science, 2011Co-Authors: Allan N Soriano, Rhoda B Leron, Menghui LiAbstract:Abstract New data on electrolytic conductivity, κ , and Molar Heat Capacity, C P , for aqueous solutions of ionic liquids, 1-ethyl-3-methylimidazolium ethylsulfate [Emim][EtSO 4 ] and 1-ethyl-3-methylimidazolium trifluoromethanesulfonate [Emim][CF 3 SO 3 ] obtained using a commercial conductivity meter and differential scanning calorimeter were reported here for temperature up to 353.2 K. The estimated measurement uncertainties for κ and C P were 1 and 2%, respectively. The present κ and C P data were reported as functions of temperature and composition. A modified empirical equation was used to correlate the temperature and composition dependence of the present κ data. An excess Molar Heat Capacity, C P E , expression using the Redlich–Kister type equation for the latter’s temperature and composition dependence was used to represent the measured C P and C P E of the considered solvent systems. The applied correlations represented the κ and C P measurements satisfactorily as indicated by an overall average deviation of 1.9 and 0.1%, respectively.
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Molar Heat Capacity of four aqueous ionic liquid mixtures
Thermochimica Acta, 2011Co-Authors: Allan N Soriano, Rhoda B LeronAbstract:Abstract As a continuation of our systematic study on physicochemical characterization of aqueous solution of ionic liquids, new measurements of Molar Heat Capacity for aqueous solutions of four ionic liquids were reported. The investigated ionic liquids were 1-butyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium bromide, 1-butyl-2,3-dimethylimidazolium tetrafluoroborate, and 1-butyl-2,3-dimethylimidazolium hexafluorophosphate. The Molar Heat capacities were measured at standard pressure and over the temperature range (303.2–353.2) K using a differential scanning calorimeter (DSC) having an estimated experimental uncertainty of about ±2% with liquid water as reference. The measured Molar Heat capacities were reported as function of temperature and composition and the excess Molar Heat capacities were calculated using a Redlich–Kister type equation. For the studied ionic liquids, results showed variations in the dependence of the excess Molar Heat capacities on temperature and composition. The applied correlation satisfactorily represented the Molar Heat Capacity measurements as shown by an acceptable overall average deviation of 0.09%.
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electrolytic conductivity and Molar Heat Capacity of two aqueous solutions of ionic liquids at room temperature measurements and correlations
The Journal of Chemical Thermodynamics, 2010Co-Authors: Allan N Soriano, Rhoda B Leron, Menghui LiAbstract:Abstract As part of our systematic study on physicochemical characterization of ionic liquids, in this work, we report new measurements of electrolytic conductivity and Molar Heat Capacity for aqueous solutions of two 1-ethyl-3-methylimidazolium-based ionic liquids, namely: 1-ethyl-3-methylimidazolium dicyanamide and 1-ethyl-3-methylimidazolium 2-(2-methoxyethoxy) ethylsulfate, at normal atmospheric condition and for temperatures up to 353.2 K. The electrolytic conductivity and Molar Heat Capacity were measured by a commercial conductivity meter and a differential scanning calorimeter (DSC), respectively. The estimated experimental uncertainties for the electrolytic conductivity and Molar Heat Capacity measurements were ±1% and ±2%, respectively. The property data are reported as functions of temperature and composition. A modified empirical equation from another researcher [1] was used to correlate the temperature and composition dependence of the our electrolytic conductivity results. An excess Molar Heat Capacity expression derived using a Redlich–Kister type equation was used to represent the temperature and composition dependence of the measured Molar Heat Capacity and calculated excess Molar Heat Capacity of the solvent systems considered. The correlations applied represent the our measurements satisfactorily as shown by an acceptable overall average deviation of 6.4% and 0.1%, respectively, for electrolytic conductivity and Molar Heat Capacity.
Chenyang Zhu - One of the best experts on this subject based on the ideXlab platform.
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experimental and correlational study of isobaric Molar Heat capacities of fatty acid esters ethyl nonanoate and ethyl dodecanoate
Fluid Phase Equilibria, 2019Co-Authors: Xiangyang Liu, Chenyang Zhu, Feng YangAbstract:Abstract An experimental study on the isobaric Molar Heat capacities of ethyl nonanoate and ethyl dodecanoate was performed at temperatures between 303 K and 393 K and at pressures between 0.1 MPa and 25.2 MPa. An increase of isobaric Molar Heat Capacity with temperature increase was observed, and temperature was found to have a greater effect on isobaric Molar Heat Capacity than pressure. Then the isobaric Molar Heat Capacity data of 18 saturated fatty acid methyl and ethyl esters in literature were selected, to get a general correlation for the isobaric Molar Heat Capacity of saturated fatty acid alkyl esters. The average absolute relative deviation and the maximum deviation of the present correlation from experimental data are lower than 0.70% and 3.82%, respectively. At last, to test the predictive ability of the proposed correlation, the Heat capacities of ethyl nonanoate and ethyl dodecanoate were calculated. The average absolute relative deviation and the maximum deviation from our experimental results are 0.88% and 2.10%, respectively.
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Isobaric Molar Heat Capacity of Ethyl Octanoate and Ethyl Decanoate at Pressures up to 24 MPa
Journal of Chemical & Engineering Data, 2018Co-Authors: Chenyang Zhu, Feng Yang, Xiangyang LiuAbstract:The isobaric Molar Heat capacities of ethyl octanoate and ethyl decanoate were determined at T = 294–354 K and p = 0.1–24 MPa. The measurements were conducted by a flow calorimeter. The measured results were in good agreements with several available experimental data at atmosphere pressure and the calculated results at high pressure in literatures. Furthermore, a fitting equation was presented to calculate the Cp of ethyl octanoate and ethyl decanoate. The maximum absolute relative deviations between experimental results and calculated data are lower than 0.4%.
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isobaric Molar Heat capacities of 1 ethyl 3 methylimidazolium acetate and 1 hexyl 3 methylimidazolium acetate up to 16 mpa
Fluid Phase Equilibria, 2016Co-Authors: Xiangyang Liu, Chenyang ZhuAbstract:Abstract Isobaric Molar Heat capacities of 1-ethyl-3-methylimidazolium acetate ([C1C2Im][OAc]) and 1-hexyl-3-methylimidazolium acetate ([C1C6Im][OAc]) were measured in the temperature range T = (303–393) K and at pressures up to 16 MPa. The relative expanded uncertainty of the isobaric Molar Heat Capacity is estimated to be less than 1%. Based on the experimental data in our work and from literature, the isobaric Molar Heat capacities of [C1C2Im][OAc] and [C1C6Im][OAc] were found to rise with the increasing temperature and the carbon atoms number on the cations, and fall with the increasing pressure. Correlations based on the experimental data were promoted to evaluate the Heat Capacity of [C1C2Im][OAc] and [C1C6Im][OAc], the absolute relative deviation between calculation and experimental data is less than 1%.
Xiangyang Liu - One of the best experts on this subject based on the ideXlab platform.
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experimental and correlational study of isobaric Molar Heat capacities of fatty acid esters ethyl nonanoate and ethyl dodecanoate
Fluid Phase Equilibria, 2019Co-Authors: Xiangyang Liu, Chenyang Zhu, Feng YangAbstract:Abstract An experimental study on the isobaric Molar Heat capacities of ethyl nonanoate and ethyl dodecanoate was performed at temperatures between 303 K and 393 K and at pressures between 0.1 MPa and 25.2 MPa. An increase of isobaric Molar Heat Capacity with temperature increase was observed, and temperature was found to have a greater effect on isobaric Molar Heat Capacity than pressure. Then the isobaric Molar Heat Capacity data of 18 saturated fatty acid methyl and ethyl esters in literature were selected, to get a general correlation for the isobaric Molar Heat Capacity of saturated fatty acid alkyl esters. The average absolute relative deviation and the maximum deviation of the present correlation from experimental data are lower than 0.70% and 3.82%, respectively. At last, to test the predictive ability of the proposed correlation, the Heat capacities of ethyl nonanoate and ethyl dodecanoate were calculated. The average absolute relative deviation and the maximum deviation from our experimental results are 0.88% and 2.10%, respectively.
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Isobaric Molar Heat Capacity of Ethyl Octanoate and Ethyl Decanoate at Pressures up to 24 MPa
Journal of Chemical & Engineering Data, 2018Co-Authors: Chenyang Zhu, Feng Yang, Xiangyang LiuAbstract:The isobaric Molar Heat capacities of ethyl octanoate and ethyl decanoate were determined at T = 294–354 K and p = 0.1–24 MPa. The measurements were conducted by a flow calorimeter. The measured results were in good agreements with several available experimental data at atmosphere pressure and the calculated results at high pressure in literatures. Furthermore, a fitting equation was presented to calculate the Cp of ethyl octanoate and ethyl decanoate. The maximum absolute relative deviations between experimental results and calculated data are lower than 0.4%.
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isobaric Molar Heat capacities of 1 ethyl 3 methylimidazolium acetate and 1 hexyl 3 methylimidazolium acetate up to 16 mpa
Fluid Phase Equilibria, 2016Co-Authors: Xiangyang Liu, Chenyang ZhuAbstract:Abstract Isobaric Molar Heat capacities of 1-ethyl-3-methylimidazolium acetate ([C1C2Im][OAc]) and 1-hexyl-3-methylimidazolium acetate ([C1C6Im][OAc]) were measured in the temperature range T = (303–393) K and at pressures up to 16 MPa. The relative expanded uncertainty of the isobaric Molar Heat Capacity is estimated to be less than 1%. Based on the experimental data in our work and from literature, the isobaric Molar Heat capacities of [C1C2Im][OAc] and [C1C6Im][OAc] were found to rise with the increasing temperature and the carbon atoms number on the cations, and fall with the increasing pressure. Correlations based on the experimental data were promoted to evaluate the Heat Capacity of [C1C2Im][OAc] and [C1C6Im][OAc], the absolute relative deviation between calculation and experimental data is less than 1%.