Phase Behavior for the CO2+ Methyl Methoxyacetate and CO2+

Feb 12, 2016 - Department of Chemical and Biomolecular Engineering, Chonnam National University, Yeosu, Jeonnam 59626, South Korea. •S Supporting ...
5 downloads 0 Views 2MB Size
Download PDF
Article pubs.acs.org/jced

Phase Behavior for the CO2 + Methyl Methoxyacetate and CO2 + Methyl trans-3-Methoxyacrylate Systems at Pressures from (5 to 20) MPa and Various Temperatures Seok-Hyun Kim, Danbi Chun, Soon-Do Yoon, and Hun-Soo Byun* Department of Chemical and Biomolecular Engineering, Chonnam National University, Yeosu, Jeonnam 59626, South Korea S Supporting Information *

ABSTRACT: Acetate and acrylate are compounds with weak polarity which show a nonideal behavior. Phase equilibria of these systems play a significant role as organic solvents in industrial processes. In this work, the solubility behavior for the (CO2 + methyl methoxyacetate) and (CO2 + methyl trans3-methoxyacrylate) mixtures at pressures from (5 to 20) MPa and various temperatures (313.2, 333.2, 353.2, 373.2, and 393.2 K) are measured in the static method with a variablevolume high pressure view cell. The experimental results obtained in this research are correlated with Peng−Robinson equation of state and van der Waals one-fluid mixing rule containing two adjustable interaction parameters. The critical constants for the Peng−Robinson equation of state were estimated using the group contributions method. The Lee−Kesler method was used to predict the acentric factor.

1. INTRODUCTION To offer thermodynamic information, the knowledge of phase behavior in binary mixtures containing supercritical fluids is required for the practical application of separation processes, polymerization processes, supercritical fluid extraction, and related industry.1−4 In particular, methyl methoxyacetate monomers have been mainly used in the manufacture of pharmaceuticals and plant protecting agents.5 Methyl trans-3methoxyacrylate monomers have been also used for a medicine intermediate of cephalosporin and medical, surgical, or other patient oriented applications.6 Phase equilibrium in binary systems containing supercritical fluids is available for a wide range of applications. Supercritical CO2 among supercritical solvents has been recommended as a solvent picked for many industrial applications because it is not only an eco-friendly, nonhazardous, affordable, and nonpoison solvent with a nonpolar molecule,7 but also a solvent with a quadrupole moment and no dipole moment.8 Experimental phase equilibrium data for the binary mixtures in supercritical CO2 have been measured on the BP (bubblepoint), DP (dew-point), and CP (critical-point) curves.9,10 The information on thermodynamics on the mixtures for the CO2 + acetate (or acrylate) monomer mixtures is required for actual uses. Experimental data for the supercritical CO2 + methoxyacetate (or methoxyacrylate) monomer systems is important for polymer processes and polymerization conditions. The vapor− liquid equilibria data for the CO2 + acetate (or acrylate) systems were reported by Jang et al.,11 McHugh et al.,12 Yoon et al.,13 Peper et al.14 and Vazquez da Silva et al.15 The major aim of this research was to understand the experimental data for the (CO2 + methyl methoxyacetate) and © 2016 American Chemical Society

(CO2 + methyl trans-3-methoxyacrylate) mixtures at high pressure. The experimental data for the (CO2 + methyl methoxyacetate) and (CO2 + methyl trans-3-methoxyacrylate) systems obtained in this research are correlated with the Peng− Robinson equation of state16 using a van der Waals one-fluid mixing rule that includes two (kij and ηij) adjustable parameters. The Joback−Lydersen method with group contributions, and Lee and Kesler method17 are used to estimate the acentric factor, critical pressure, and temperature of methyl methoxyacetate and methyl trans-3-methoxyacrylate.

2. EXPERIMENTAL SECTION Experimental Apparatus and Procedure. Figure 1 shows the schematic diagram of a high-pressure phase equilibrium apparatus used in this work. The apparatus and techniques used to measure the phase equilibria of methyl methoxyacetate and methyl trans-3-methoxyacrylate in supercritical CO2 are described in detail elsewhere.18,19 A static-type apparatus with variable-volume view cell used operated pressures up to 200.0 MPa to measure the phase equilibria data. A high pressure gas cylinder (bomb) is used with the standard uncertainty of 0.002 g to add supercritical CO2 to the cell. After the empty cell was purged 2−3 times with CO2 and N2 to remove traces of organic matter, the monomers were loaded into the cell using a syringe with the standard uncertainty of 0.0008. The solution is compressed to the desired pressure by moving the piston (2.54 cm length) located Received: August 23, 2015 Accepted: February 1, 2016 Published: February 12, 2016 1101

DOI: 10.1021/acs.jced.5b00711 J. Chem. Eng. Data 2016, 61, 1101−1108

Journal of Chemical & Engineering Data

Article

Figure 1. Schematic diagram of the experimental apparatus used in this work.

(400 MHz, CDCl3) δ: 3.70 (CH3, −OC(O)−CC), 3.90 (CH3, −O−CC), 5.20 (H, 1-ethylene), 7.60 (H, 1-ethylene). Two components were used without further purification. The chemicals used in this work are shown specifically in Table 1.

within the cell using water pressurized by a high pressure generator (HIP, model 37-5.75-60). The pressure of the mixture is measured with a Heise gauge (Dresser Ind., model CM-53920, 0 to 34.0 MPa, the standard uncertainty of 0.02 MPa). The system temperature, typically maintained with the standard uncertainty of 0.2 K, was measured using a platinumresistance thermometer (Thermometrics Corp., Class A) and a digital multimeter (Yokogawa, model 7563, the relative standard uncertainty being 0.005%). The contents of the cell were visible on a video monitor using a camera coupled to a borescope (Olympus Corp., model F100-038-000-50) placed directly against the sapphire window. At a fixed temperature, the solution was compressed to one (single) phase. The solution was maintained in the one phase region at the desired temperature for a minimum of 30−40 min to allow the cell to approach phase equilibrium. Then, the pressure was slowly decreased until two phases appeared. When dropping pressure from one phase to two phases, we drop a pressure very slowly near the two phases. The real pressure drop is operated by a pressure generator. As mentioned in the Experimental Section, the measurement instrument was Heise gauge. To determine BP(bubble point), DP(dew point), and CP(critical point), a BP pressure was obtained when small vapor bubbles appeared in the cell, while a DP was obtained after a fine mist appeared. To obtain mixture-CP, the temperature and pressure of the mixture was adjusted until critical opalescence was observed along with equal liquid and vapor volume upon formation of the second phases. Materials. CO2 (>0.999 mass fraction purity, CAS RN 12438-9) was purchased from Deokyang Co. and used as received. Methyl methoxyacetate (>0.980 mass fraction purity, CAS RN 6290-49-9) and methyl 3-methoxyacrylate were purchased from Wako Pure Chemical Industrial, Ltd. We analyzed the methyl 3-methoxyacrylate monomer with a 1H NMR spectrometer (model: AVANCE III HD 400), and the result confirmed that it is the methyl trans-3-methoxyacrylate (>0.950 mass fraction purity, CAS RN 5788-17-0). The 1H NMR spectrum is presented in the Supporting Information (Figure S1). 1H NMR

Table 1. Specifications of the Chemical Used chemical name

source

CO2 methyl methoxyacetate

Deok Yang Co. Wako Pure Chemical Industrial, Ltd. Wako Pure Chemical Industrial, Ltd.

methyl trans-3methoxyacrylate

mass fraction puritya

purification method

analysis methoda

> 0.999 > 0.980

none none

GCb

> 0.950

none

GCb

a

Both the analysis method and the mass fraction purity were provided by the suppliers. bGas−liquid chromatography.

3. EXPERIMENTAL RESULTS AND DISCUSSION Experimental phase behavior data on the methyl methoxyacetate and methyl trans-3-methoxyacrylate in supercritical CO2 were reported. The standard uncertainties were estimated to pressure at u(p) = 0.2 MPa and temperature at u(T) = 0.12 K.20,21 The standard uncertainties of methyl methoxyacetate and methyl trans-3-methoxyacrylate mole fractions were estimated u(x) = 0.0008.20 To date, the experimental data for the CO2 + methyl methoxyacetate and CO2 + methyl trans-3methoxyacrylate systems have not been published in the literature. Figure 2a and Table 2 show the experimental pressure− composition (P, x) isotherms at T = (313.2, 333.2, 353.2, 373.2 and 393.2) K, and pressures ranging from (5.28 to 18.79) MPa for the (CO2 + methyl methoxyacetate) system. In Figure 2a, three phases were not observed in the five temperatures. The mixture-critical pressures are 13.69 MPa at T = 353.2 K, 16.48 MPa at T = 373.2 K and 18.79 MPa at T = 393.2 K. The (p, x) isotherms shown in Figure 2a are consistent with those 1102

DOI: 10.1021/acs.jced.5b00711 J. Chem. Eng. Data 2016, 61, 1101−1108

Journal of Chemical & Engineering Data

Article

P=

a(T ) RT − V−b V (V + b) + b(V − b)

a(T ) = 0.457235

b = 0.077796

α(T )R2Tc2 pc

(1)

(2)

RTc pc

(3)

α(T ) = [1 + κ(1 − Tr0.5)]2

(4)

κ = 0.37464 + 1.54226ω − 0.26992ω 2

(5)

where Tc, pc, and ω are the critical temperature, critical pressure, and acentric factor of the pure component, respectively. The Peng−Robinson equation of state was used with the following a van der Waals one-fluid mixing rules. amix =

∑ ∑ xixjaij i

(6)

j

aij = (aiiajj)1/2 (1 − kij)

bmix =

∑ ∑ xixjbij i

bij =

Figure 2. Plot of pressure against mole fraction that compares the experimental data (symbols) of the (carbon dioxide + methyl methoxyacetate) {(1 - x) CO2 + x CH3OCH2COOCH3} system (a) and (carbon dioxide + methyl trans-3-methoxyacrylate) {(1 - x) CO2 + x CH3OCHCHCOOCH3} system (b) with calculations (solid lines) obtained with the Peng−Robinson equation of state; kij = 0.036, ηij = −0.043 (carbon dioxide + methyl methoxyacetate) and kij = 0.033, ηij = −0.053 (carbon dioxide + methyl trans-3-methoxyacrylate). red ●, 313.2 K; blue ■, 333.2 K; green ▲, 353.2 K; dark green ▼, 373.2 K; maroon ◆, 393.2 K.

(7)

(8)

j

1 (bii + bjj)(1 − ηij) 2

(9)

where aii, ajj, bii, and bjj were pure component parameters as defined by Peng−Robinson equation,16 and kij and ηij were two component (i and j) interaction parameters determined by fitting (p, x) isotherms curves. The OF (objection function) and RMSD (root mean squared relative deviation) percent of this calculation were defined by ⎛ Pexp − Pcal ⎞2 ⎟ OF = ∑ ⎜⎜ Pexp ⎟⎠ i ⎝ N

anticipated for a type-I region,22,23 in which a maximum takes place in the mixture-critical curve. The type-I phase diagram for a binary mixture is the simplest behavior. The apparent characteristics of the type-I curve are that only one phase exists throughout the phase diagram and that the mixture-critical curve runs continuously from the critical-point of the CO2 component to that of the methyl methoxyacetate and methyl trans-3-methoxyacrylate components. The solubility curve of CO2 decreases as the temperatures shift higher under a fixed pressure. Figure 2b and Table 3 show the experimental equilibria data at T = (313.2, 333.2, 353.2, 373.2 and 393.2) K, and at pressures from (5.38 to 19.96) MPa for the (CO2 + methyl trans-3-methoxyacrylate) mixture. In Figure 2b, the critical mixture pressures are 15.14 MPa (at T = 353.2 K), 17.86 MPa (at T = 373.2 K) and 19.96 MPa (at T = 393.2 K). The (CO2 + methyl trans-3-methoxyacrylate) system does not display three phases at the various temperatures investigated. The critical mixture curve for the (CO2 + methyl trans-3-methoxyacrylate) system exhibits maximum pressure in (p, T) space. In this research, the phase behavior data are correlated by using the Peng−Robinson equation of state. At this point, the Peng−Robinson equations of state are briefly described. The Peng−Robinson equation of state16 is expressed as follows:

RMSD(%) =

OF × 100 ND

(10)

(11)

The pure component molecular weight (Mw), critical temperatures (Tc), critical pressures (pc), and acentric factors (ω) for CO2,17 methyl methoxyacetate,17 and methyl trans-3-methoxyacrylate17 are described in Table 4, and all of them were used with the Peng−Robinson equation of state. The boiling points of two chemicals were found from the literature.24,25 The Joback and Lyderson group-contribution method17 was used to calculate the critical properties of methyl methoxyacetate and methyl trans-3-methoxyacrylate and the Lee− Kesler method17 is used the vapor pressures to calculate. Figure 3 shows the comparison of experimental values for the (CO2 + methyl methoxyacetate) (a) and (CO2 + methyl trans3-methoxyacrylate) (b) systems and estimated values obtained using the Peng−Robinson equation of state at 353.2 K. The interaction parameters (kij and ηij) for the binary system of the Peng−Robinson equation were fitted with the experimental results at 353.2 K. The optimized parameters of the Peng− Robinson equation for the (CO2 + methyl methoxyacetate) (a) and (CO2 + methyl trans-3-methoxyacrylate) (b) systems were kij = 0.036 and ηij = −0.043 (number of experimental data = 17, 1103

DOI: 10.1021/acs.jced.5b00711 J. Chem. Eng. Data 2016, 61, 1101−1108

Journal of Chemical & Engineering Data

Article

Table 2. Experimental Data of Pressure−Composition Isotherms for (Carbon Dioxide + Methyl Methoxyacetate) {(1 - x)CO2 + xCH3OCH2COOCH3} System x

pa/MPa

transitionb

x

BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP

0.212 0.269 0.321 0.338 0.387 0.427 0.473 0.523 0.567

a

0.065 0.070 0.073 0.091 0.106 0.125 0.139 0.155 0.174 0.206 0.212 0.269 0.321 0.338 0.387 0.427 0.473 0.523 0.567 0.065 0.070 0.073 0.091 0.106 0.125 0.139 0.155 0.174 0.206 0.212 0.269 0.321 0.338 0.387 0.427 0.473 0.523 0.567 0.070 0.091 0.106 0.125 0.139 0.155 0.174 0.206

T = 313.2 K 8.21 8.19 8.17 8.10 7.90 7.76 7.65 7.57 7.55 7.35 7.21 6.66 6.24 6.16 6.10 5.88 5.63 5.42 5.28 T = 333.2 K 11.09 11.00 10.95 10.79 10.66 10.46 10.20 10.11 9.79 9.55 9.47 8.72 8.34 8.22 7.69 7.33 7.04 6.66 6.38 T = 353.2 K 13.46 13.69 13.69 13.48 13.32 13.23 12.95 12.47

0.070 0.091 0.106 0.125 0.139 0.155 0.174 0.206 0.212 0.269 0.321 0.338 0.387 0.427 0.473 0.523 0.567

BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP

0.070 0.091 0.106 0.125 0.139 0.155 0.206 0.212 0.269 0.321 0.338 0.387 0.427 0.473 0.523 0.567

DP CP BP BP BP BP BP BP

pa/MPa

transitionb

T = 353.2 K 12.36 11.21 10.50 10.39 9.69 9.02 8.59 7.90 7.55 T = 373.2 K 15.49 16.23 16.48 16.39 16.13 15.73 15.30 14.68 14.50 13.55 12.75 12.49 11.55 10.66 10.10 9.28 8.59 T = 393.2 K 15.83 17.75 18.63 18.79 18.55 18.22 17.11 17.00 15.82 14.92 14.55 13.48 12.45 11.52 10.45 9.62

BP BP BP BP BP BP BP BP BP DP DP CP BP BP BP BP BP BP BP BP BP BP BP BP BP BP DP DP DP CP BP BP BP BP BP BP BP BP BP BP BP BP

a Standard uncertainties are u(T) = 0.12 K, u(p) = 0.2 MPa and u(x) = 0.0008. bBP, bubble-point; CP, critical-point; DP, dew-point.

RMSD = 5.11%), and kij = 0.033 and ηij = −0.053 (number of experimental data = 16, RMSD = 3.12%), respectively. Figure 2a compares the experimental results with calculated (p, x) isotherms at the temperatures of T = (313.2, 333.2, 353.2, 373.2 and 393.2) K for the (CO 2 + methyl methoxyacetate) system using the optimized kij and ηij values (number of experimental data = 17, RMSD = 5.11%) determined at 353.2 K. In Figure 2a, obtained data were wellfitted with the Peng−Robinson equation using optimized

parameters for the (CO2 + methyl methoxyacetate) system (number of experimental data = 89, RMSD = 5.78%). Figure 2b compares the experimental values with predicted (p, x) isotherms at temperatures of T = (313.2, 333.2, 353.2, 373.2 and 393.2) K for the (CO2 + methyl trans-3methoxyacrylate) system. In the same manner as above, these isotherms were predicted using the optimized values of kij = 0.033 and ηij = −0.053 (number of experimental data = 16, RMSD = 3.12%) decided at 353.2 K. The RMSD values for the 1104

DOI: 10.1021/acs.jced.5b00711 J. Chem. Eng. Data 2016, 61, 1101−1108

Journal of Chemical & Engineering Data

Article

Table 3. Experimental Data of Pressure−Composition Isotherms for (Carbon Dioxide + Methyl trans-3-Methoxyacrylate) {(1 − x)CO2 + xCH3OCHCHCOOCH3} System x

pa/MPa

transitionb

x

BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP

0.361 0.424 0.479 0.530 0.589 0.655

a

0.032 0.054 0.081 0.102 0.118 0.141 0.171 0.204 0.263 0.312 0.361 0.424 0.479 0.530 0.589 0.655 0.032 0.054 0.081 0.102 0.118 0.141 0.171 0.204 0.263 0.312 0.361 0.424 0.479 0.530 0.589 0.655 0.032 0.054 0.081 0.102 0.118 0.141 0.171 0.204 0.263 0.312

T = 313.2 K 8.50 8.49 8.48 8.45 8.41 8.38 8.31 8.10 7.90 7.52 7.28 6.66 6.59 6.24 5.62 5.38 T = 333.2 K 11.78 11.76 11.69 11.62 11.62 11.35 11.21 10.80 10.38 9.55 9.14 8.31 7.90 7.41 6.66 6.28 T = 353.2 K 14.88 15.14 15.03 15.03 15.01 14.86 14.76 14.03 13.21 12.24

0.032 0.054 0.081 0.102 0.118 0.141 0.171 0.204 0.263 0.312 0.361 0.424 0.479 0.530 0.589 0.655

BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP BP

0.032 0.054 0.081 0.102 0.118 0.141 0.171 0.204 0.263 0.312 0.361 0.424 0.479 0.530 0.589 0.655

DP CP BP BP BP BP BP BP BP BP

pa/MPa

transitionb

T = 353.2 K 11.48 10.17 9.48 8.66 7.90 7.07 T = 373.2 K 17.17 17.69 17.86 17.84 17.81 17.69 17.35 16.97 15.97 14.66 13.62 12.21 11.21 10.03 9.07 7.97 T = 393.2 K 18.01 19.41 19.90 19.96 19.93 19.83 19.59 19.28 18.31 16.86 15.76 14.03 12.79 11.35 10.24 8.83

BP BP BP BP BP BP DP DP CP BP BP BP BP BP BP BP BP BP BP BP BP BP DP DP DP CP BP BP BP BP BP BP BP BP BP BP BP BP

a Standard uncertainties are u(T) = 0.12 K, u(p) = 0.2 MPa and u(x) = 0.0008. bBP, bubble-point; CP, critical-point; DP, dew-point.

Table 4. Pure Component Properties for the Peng-Robinson Equation of State

a

Chem Blink. bChemSynthesis. 1105

DOI: 10.1021/acs.jced.5b00711 J. Chem. Eng. Data 2016, 61, 1101−1108

Journal of Chemical & Engineering Data

Article

Figure 4. Plot of pressure against mole fraction that compares the experimental data (symbols) of the (carbon dioxide + methyl methoxyacetate) {(1 − x)CO2 + xCH3OCH2COOCH3} (a) and (carbon dioxide + methyl trans-3-methoxyacrylate) {(1 − x)CO2 + xCH3OCHCHCOOCH3} (b) systems with calculations (solid lines) obtained with the Peng−Robinson equation of state using optimum parameters (kij and ηij) at each temperatures. red ●, 313.2 K; blue ■, 333.2 K; green ▲, 353.2 K; dark green ▼, 373.2 K; maroon ◆, 393.2 K.

Figure 3. Plot of pressure against mole fraction that compares the experimental data (symbols) of the (carbon dioxide + methyl methoxyacetate) {(1 − x)CO2 + xCH3OCH2COOCH3} (a) and (carbon dioxide + methyl trans-3-methoxyacrylate) {(1 − x)CO2 + xCH3OCHCHCOOCH3}(b) systems with calculations obtained from the Peng−Robinson equation of state with kij and ηij set equal to zero (blue dashed lines), kij = 0.036, ηij = −0.043 (carbon dioxide + methyl methoxyacetate) and kij = 0.033, ηij = −0.053 (carbon dioxide + methyl trans-3-methoxyacrylate) (red solid lines) at 353.2 K.

(CO2 + methyl trans-3-methoxyacrylate) system using two parameters determined at five temperatures were 7.01%. Here, the number of experimental data is 80 points at five temperatures. The curves predicted by the Peng−Robinson equation of state did not display vapor−liquid−liquid (three) phases at the five temperatures. Figure 4 plots the pressures against mole fraction to compare the experimental result (symbols) of the (CO2+ methyl methoxyacetate) (a) and (CO2 + methyl trans-3-methoxyacrylate) (b) mixtures with calculations (solid lines) obtained with the Peng−Robinson equation using optimum parameters (kij and ηij) at each temperature. As shown in Figure 4, these curves were predicted using optimized parameters decided at each temperature. RMSD at various temperatures (313.2, 333.2, 353.2, 373.2, and 393.2 K) for the (CO2 + methyl methoxyacetate) (a) system was 3.89% (at 313.2 K, data point no. = 19), 3.54% (at 333.2 K, data point no. = 19), 5.11% (at 353.2 K, data point no. = 17), 4.68% (at 373.2 K, data point no. = 17) and 4.70% (at 393.2 K, data point no. = 17), respectively. The RMSD values at five temperatures for the (CO2 + methyl trans-3-methoxyacrylate) (b) system were 3.54%, 3.85%, 3.12%, 2.83% and 4.38%, respectively. Here, number of experimental data is 16 at each temperature. The comparison between the experimental results and predicted curve shows a good agreement at various temperatures.

According to predicted results, the mixture-critical curve was the type-I region.22,23 Figure 5 compares the mixture-critical curves of the experimental results with predicted values by the Peng− Robinson equation for the (CO2 + methyl methoxyacetate) and (CO2 + methyl trans-3-methoxyacrylate) systems using adjusted interaction parameters (kij and ηij) at 353.2 K. The predicted mixture-critical curve is a type-I region. Solid lines represent the vapor pressure of pure CO2 and methyl methoxyacetate (a) or CO2 and methyl trans-3-methoxyacrylate (b). The solid lines signify the vapor pressure of pure CO2,17 methyl methoxyacetate17 and methyl trans-3-methoxyacrylate17 obtained by the Lee−Kesler method.14 The solid circles signify the critical point of pure CO2, methyl methoxyacetate, and methyl trans-3-methoxyacrylate. The upper region of the dash line is one phase (fluid), the lower region of it vapor−liquid (two phases). The dash lines represent the predicted values obtained from the Peng−Robinson equation of state, with kij = 0.036 and ηij = −0.043 (CO2 + methyl methoxyacetate) (a) and kij = 0.033 and ηij = −0.053 (CO2 + methyl trans-3methoxyacrylate) (b). The closed squares (blue) are the mixture-critical points determined from isotherms in this experiment measured. 1106

DOI: 10.1021/acs.jced.5b00711 J. Chem. Eng. Data 2016, 61, 1101−1108

Journal of Chemical & Engineering Data

■

Article

ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.jced.5b00711. NMR spectrum of analyzed methyl trans-3-methoxyacrylate (PDF)

■

AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. Tel.: +82.61.659.7296. Fax: +82.61.653.3659. Funding

This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (Grant No. NRF-2014R1A1A2A10055673). Notes

The authors declare no competing financial interest.

■

REFERENCES

(1) Wichterle, I. Phase equilibria with supercritical components. Pure Appl. Chem. 1993, 65, 1003−1008. (2) Byun, H. S.; Hasch, B. M.; McHugh, M. A.; Mahling, F. O.; Busch, M.; Buback, M. Poly(ethylene-co-butyl acrylate): phase behavior in ethylene compared to the poly(ethylene-co-methyl acrylate)-ethylene system and aspects of copolymerization kinetics at high-pressures. Macromolecules 1996, 29, 1625−1632. (3) Kiran, E. Polymer miscibility, phase separation, morphological modifications and polymorphic transformations in dense fluids. J. Supercrit. Fluids 2009, 47, 466−483. (4) Rindfleisch, F.; DiNoia, T. P.; McHugh, M. A. Solubility of polymers and copolymers in supercritical CO2. J. Phys. Chem. 1996, 100, 15581−15587. (5) Gregorowicz, J.; Fermeglia, M.; Soave, G.; Kikic, I. The perturbed hard chain theory for the prediction of supercritical fluid extraction: pure component properties. Chem. Eng. Sci. 1991, 46, 1427−1436. (6) (a) http://www.phtchemical.com/pdf/PHT_specs_(MAA)ash. pdf (accessed August 2015). (b) http://www.coleparmer.com/ Product/Methyl_3_Methoxyacrylate_25_GM/EW-00032-JK (accessed August 2015). (7) McHugh, M. A.; Krukonis, V. J. Supercritical Fluid Extraction, 2nd ed.; Butterworth-Heinemann: Stoneham, 1994. (8) Prausnitz, J. M.; Lichtenthaler, R. N.; Gomes de Azevedo, E. Molecular Thermodynamics of Fluid-Phase Equilibria, 3rd ed.; PrenticeHall, Inc.: Englewood Cliffs, NJ, 1998. (9) Cho, S. H.; Yoon, S. D.; Byun, H. S. Bubble-point measurement for the CO2+diethylene glycol diacrylate and CO2+diethylene glycol dimethacrylate systems at high pressure. Korean J. Chem. Eng. 2013, 30, 739−745. (10) Kim, S. H.; Jang, Y. S.; Yoon, S. D.; Byun, H. S. High pressure phase behavior for the binary mixture of valeronitrile, capronitrile and lauronitrile in supercritical carbon dioxide at temperatures from 313.2 to 393.2 K and pressures from 3.9 to 25.7 MPa. Fluid Phase Equilib. 2011, 312, 93−100. (11) Jang, Y. S.; Choi, Y. S.; Byun, H. S. Phase behavior for the poly(2-methoxyethyl acrylate)+supercritical solvent + cosolvent mixture and CO2 + 2-methoxyethyl acrylate system at high pressure. Korean J. Chem. Eng. 2015, 32, 958−966. (12) McHugh, M. A.; Rindfleisch, F.; Kuntz, P. T.; Schmaltz, C.; Buback, M. Cosolvent effect of alkyl acrylates on the phase behaviour of poly (alkyl acrylates)−supercritical CO2 mixtures. Polymer 1998, 39, 6049−6052. (13) Yoon, S. D.; Kim, C. R.; Byun, H. S. Phase behavior of binary mixture for the isoalkyl acetate in supercritical carbon dioxide. Fluid Phase Equilib. 2014, 365, 97−105.

Figure 5. Plot of pressure against temperature for the (carbon dioxide + methyl methoxyacetate) {(1 − x)CO2 + xCH3OCH2COOCH3} (a) and (carbon dioxide + methyl trans-3-methoxyacrylate) {(1 − x)CO2 + xCH3OCHCHCOOCH3} (b) systems. Solid lines and circles represent the vapor−liquid lines and critical points for pure CO2 and methyl methoxyacetate (a) or carbon dioxide and methyl trans-3methoxyacrylate (b). Closed squares (blue) are critical points determined from isotherms measured in this work. Dashed lines represent calculations obtained using the Peng−Robinson equation of state with kij = 0.036, ηij = −0.043 (carbon dioxide + methyl methoxyacetate), and kij = 0.033, ηij = −0.053 (carbon dioxide + methyl trans-3-methoxyacrylate).

4. CONCLUSIONS High pressure experimental data of (P, x) isotherm for the (CO2 + methyl methoxyacetate) and (CO2 + methyl trans-3methoxyacrylate) binary systems were studied using a static apparatus of a variable-volume view cell at temperatures ranging from 313.2 to 393.2 K and pressure up to 19.96 MPa. The (CO2 + methyl methoxyacetate) and (CO2 + methyl trans-3methoxyacrylate) mixtures do not exhibit three phases at the five temperatures. The Peng−Robinson equation of state moderately predicts the phase behavior for the (CO2 + methyl methoxyacetate) and (CO2 + methyl trans-3-methoxyacrylate) systems using two temperature-independent mixture interaction parameters. The critical mixture curves between the predicted and experimental data are in reasonably good agreement when considering two adjustable parameters of the Peng−Robinson equation of state are used. The RMSD values for the (CO2 + methyl methoxyacetate) and for the (CO2 + methyl trans-3-methoxyacrylate) systems calculated by adjustable parameter at each temperature were 4.40% and 3.58% (mean error of five temperatures), respectively. 1107

DOI: 10.1021/acs.jced.5b00711 J. Chem. Eng. Data 2016, 61, 1101−1108

Journal of Chemical & Engineering Data

Article

(14) Peper, S.; Haverkamp, V.; Dohrn, R. Measurement of phase equilibria of the systems CO2 + styrene and CO2 + vinyl acetate using different experimental methods. J. Supercrit. Fluids 2010, 55, 537−544. (15) Vazquez da Silva, M.; Barbosa, D.; Ferreira, P. O. High pressure phase equilibrium data for the systems carbon dioxide/ethyl acetate and carbon dioxide/isoamyl acetate at 295.2, 303.2 and 313.2 K. Fluid Phase Equilib. 2000, 175, 19−33. (16) Peng, D. Y.; Robinson, D. B. A new two-constant equation of state. Ind. Eng. Chem. Fundam. 1976, 15, 59−63. (17) Poling, B. E.; Prausnitz, J. M.; O’Connell, J. P. The Properties of Liquids and Gases, 5th ed.; McGraw-Hill: New York, 2001. (18) Yoon, S. D.; Byun, H. S. Experimental measurement and correlation of phase behavior for the CO2+heptafluorobutyl acrylate and CO2+heptafluorobutyl methacrylate systems at high pressure. Korean J. Chem. Eng. 2014, 31, 522−527. (19) Jang, Y. S.; Kim, S. H.; Yoo, K. P.; Byun, H. S. Phase behavior measurement for the binary mixture of CO2+ neopentyl glycol diacrylate and CO2+ neopentyl glycol dimethacrylate systems at high pressure. Fluid Phase Equilib. 2011, 302, 234−240. (20) Chirico, R. D.; Frenkel, M.; Diky, V. V.; Marsh, K. N.; Wilhoit, R. C. ThermoML An XML-Based Approach for Storage and Exchange of Experimental and Critically Evaluated Thermophysical and Thermochemical Property Data. J. Chem. Eng. Data 2003, 48, 1344−1359. (21) Yoon, S. D.; Byun, H. S. Phase behaviour for the (carbon dioxide + 1,3-butanediol diacrylate) and (carbon dioxide + 1,3butanediol dimethacrylate) systems at elevated pressures and temperatures. J. Chem. Thermodyn. 2014, 71, 91−97. (22) Scott, R. L.; van Konynenburg, P. B. Static properties of solutions. van der Waals and related models for hydrocarbon mixtures. Discuss. Faraday Soc. 1970, 49, 87−97. (23) Streett, W. B. Phase Equilibria in Fluid and Solid Mixtures at High Pressure. In Chemical Engineering at Supercritical Fluid Condition; Paulaitis, M. E., Penninger, J. M. L., Gray, R. D., Davidson, P., Eds.; Ann Arbor Science: Ann Arbor: MI, 1983. (24) Catalog Handbook of Fine Chemicals; Aldrich Chemical Company Inc.: Milwaukee, WI, 2012. (25) http://www.chemsynthesis.com/base/chemical-structure15739.html (accessed August 2015).

1108

DOI: 10.1021/acs.jced.5b00711 J. Chem. Eng. Data 2016, 61, 1101−1108