Phase equilibrium for the binary azeotropic mixture of trifluoroiodomethane (R13I1) + 1,1,2,2-tetrafluoroethane (R134) at temperatures from 258.150 to 283.150 K

doi:10.1016/j.fluid.2011.11.013

Fluid Phase Equilibria

Volume 315, 15 February 2012, Pages 35-39

https://doi.org/10.1016/j.fluid.2011.11.013 Get rights and content

Abstract

Isothermal vapor–liquid equilibrium data of binary trifluoroiodomethane (R13I1) + 1,1,2,2-tetrafluoroethane (R134) systems at 258.150, 263.150, 273.150 and 283.150 K were measured by a recirculation apparatus with visual windows. The measured uncertainties of the temperature, pressure, and compositions are less than ±5 mK, ±0.0005 MPa, and ±0.005, respectively. All the experimental data were correlated by the Peng–Robinson (PR) EoS with the Huron–Vidal (HV) mixing rule utilizing the non-random two-liquid (NRTL) activity coefficient model. Azeotropic behavior can be found at the measured temperature range.

Highlights

► Isothermal vapor–liquid equilibrium data of binary R13I1 + R134 systems were measured at temperatures from 258.150 to 283.150 K. ► The apparatus used in this work is based on the vapor-phase recirculation method. ► The VLE data were correlated by the PR–HV–NRTL model. ► Azeotropic behavior can be found.

Introduction

The production and use of the traditional chlorofluorocarbons (CFCs) refrigerants have been limited because of their ozone depletion effects, so searching for the highly efficient alternative refrigerants which are friendly to the environment has become a urgent task for the refrigeration and air-conditioning industry. The investigations show that it is very hard to find pure substance candidates with appropriate properties. Therefore, mixed refrigerants especially the azeotropic mixtures become one of the most promising refrigerant candidates since their behaviors are very nearly as pure substance at their azeotropic compositions. Vapor–liquid equilibrium (VLE) data is one of the most important fundamental parameters in evaluating the performance of the mixed refrigerants and optimizing mixture compositions. In this work, the isothermal VLE data for trifluoroiodomethane (R13I1) + 1,1,2,2-tetrafluoroethane (R134) systems were measured by a recirculation apparatus at 258.150, 263.150, 273.150 and 283.150 K. The VLE data were correlated by the Peng–Robinson (PR) EoS [1] with the Huron–Vidal (HV) mixing rule [2] utilizing the non-random two-liquid (NRTL) activity coefficient model [3], and the azeotropic behavior was found. R13I1 and R134 are both nonflammable refrigerants. Their mixture can be used as potential alternative refrigerants or to mix with hydrocarbons (HCs) to reduce the flammability of the HCs. After a careful examination of the public literatures, it seems that the data of this system have not been reported.

Section snippets

Materials

R13I1 and R134 were both supplied by Nanjing Yuji Tuohao Co. with declared mole fraction purity of 0.990 and 0.995, respectively. They were used without further purification.

Experimental apparatus

As shown in Fig. 1, the apparatus used to measure the VLE data in this work is based on the vapor-phase recirculation method. The details have been described in our previous work [4], [5]. A cylindrical equilibrium cell made of stainless steel was located in the liquid bath which was full of alcohol. Glasses were fixed on

Results and correlations

All the VLE experimental data of R13I1 + R134 were correlated by the PR EoS [1] with the HV mixing rule [2] utilizing the NRTL activity coefficient model [3].

The PR EoS is given as $p = \frac{R T}{v - b} - \frac{a (T)}{v (v + b) + b (v - b)}$ where p is the pressure, R is the gas constant (R = 8.3145 J mol⁻¹ K⁻¹) [6], v is the molar volume, T is the temperature, and a and b are constants of EoS.

The constants a and b of the PR EoS are defined as $a (T) = 0.457235 \frac{R^{2} T_{c}^{2} α (T)}{p_{c}}$ $b = 0.077796 \frac{R T_{c}}{p_{c}}$ where $α (T) = {[1 + (0.37464 + 1.54226 ω - 0.26992 ω^{2}) (1 - T_{r}^{0.5})]}^{2}$ $T_{r} = \frac{T}{T_{c}}$

Conclusions

In this work, the VLE data for the binary system of R13I1 + R134 were measured with a recirculation method at four temperatures. All the data were correlated by the PR EoS with the HV mixing rule involving the NRTL activity coefficient model. The correlated results show good agreement with the experimental data at each temperature. The maximum average relative deviation of pressure is 0.38%, while the maximum average absolute deviation of vapor phase mole fraction is 0.0040. The azeotropic

Acknowledgements

This work is financially supported by the National Natural Sciences Foundation of China under the contract number of 50890183 and the National Basic Research Program of China (973 Program) (2011CB710701).

References (9)

M.J. Huron et al.
Fluid Phase Equilib.
(1979)
X.Q. Dong et al.
J. Chem. Thermodyn.
(2011)
X.Q. Dong et al.
Int. J. Refrig.
(2011)
D.Y. Peng et al.
Ind. Eng. Chem. Fundam.
(1976)

There are more references available in the full text version of this article.

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Phase equilibrium for the binary azeotropic mixture of trifluoroiodomethane (R13I1) + 1,1,2,2-tetrafluoroethane (R134) at temperatures from 258.150 to 283.150 K

Abstract

Highlights

Introduction

Section snippets

Materials

Experimental apparatus

Results and correlations

Conclusions

Acknowledgements

Fluid Phase Equilib.

J. Chem. Thermodyn.

Int. J. Refrig.

Ind. Eng. Chem. Fundam.