A Systematic Study of Cubic Equations of State with van der Waals Mixing Rules and Different Combining Rules in Predicting the Densities of LNG and Natural Gas Model Systems

In the present study, the effect of equations of state and mixing rules in a thermodynamic approach has been investigated for the correlation of the solubility of four new solid pharmaceutical compounds, namely, benzamide, cetirizine, metaxalone and niflumic acid in supercritical CO2 at different temperatures and pressures. Two equations of state, the Peng?Robinson (PR) and Soave?Redlich?Kwong (SRK), coupled with mixing rules of one-parameter van der Waals (vdW1) and two-parameter van der Waals (vdW2) were used, where the binary interaction parameters for these sets of equations were evaluated. The approach correlations and the robustness of the numerical technique were validated with the experimental data previously reported for these compounds at different temperatures and pressures. The calculated average absolute relative deviations (AARD) were 7.51 and 5.31 % for PR/vdW1 and PR/ /vdW2 couples, and 11.05 and 10.24 % for SRK/vdW1 and SRK/vdW2 couples, respectively. It was also found that the PR equation of state results in modeling performance better than the SRK equation, and the vdW2 mixing rule better than the vdW1 one. These results obviously demonstrate that the combined approach used in this study is applicable for correlation of solid solubilities of some pharmaceutical compounds in supercritical CO2. Additionally, a semiempirical correlation is proposed for estimating the solubility of drug solids in supercritical CO2 as a function of pressure and temperature.

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New insight into prediction of phase behavior of natural gas hydrate by different cubic equations of state coupled with various mixing rules

Petroleum Science ◽

10.1007/s12182-017-0190-1 ◽

2017 ◽

Vol 14 (4) ◽

pp. 780-790

Author(s):

Amir Hossein Saeedi Dehaghani

Keyword(s):

Natural Gas ◽

Phase Behavior ◽

Gas Hydrate ◽

Equations Of State ◽

Mixing Rules ◽

Natural Gas Hydrate ◽

Insight Into

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Properties of Refrigerants from Cubic Equations of State

Revista de Chimie ◽

10.37358/rc.08.5.1827 ◽

2008 ◽

Vol 59 (5) ◽

Author(s):

Viorel Feroiu ◽

Dan Geana ◽

Catinca Secuianu

Keyword(s):

Experimental Data ◽

Vapor Pressure ◽

Equations Of State ◽

Ternary Mixtures ◽

Volumetric Properties ◽

Mixing Rules ◽

Saturation Curve ◽

Equilibrium Thermodynamic ◽

Liquid Equilibrium ◽

Binary And Ternary Mixtures

Vapour � liquid equilibrium, thermodynamic and volumetric properties were predicted for three pure hydrofluorocarbons: difluoromethane (R32), pentafluoroethane (R125) and 1,1,1,2 � tetrafluoroethane (R134a) as well as for binary and ternary mixtures of these refrigerants. Three cubic equations of state GEOS3C, SRK (Soave � Redlich � Kwong) and PR (Peng � Robinson) were used. A wide comparison with literature experimental data was made. For the refrigerant mixtures, classical van der Waals mixing rules without interaction parameters were used. The GEOS3C equation, with three parameters estimated by matching several points on the saturation curve (vapor pressure and corresponding liquid volumes), compares favorably to other equations in literature, being simple enough for applications.

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Van der Waals-like Equations of State. I. Application to Pure Liquids

Polymer Journal ◽

10.1295/polymj.13.993 ◽

1981 ◽

Vol 13 (11) ◽

pp. 993-1002 ◽

Cited By ~ 9

Author(s):

Koichi Fujisawa ◽

Tomoo Shiomi ◽

Fumiyuki Hamada ◽

Akio Nakajima

Keyword(s):

Equations Of State ◽

Van Der Waals

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Enhancing Higher Hydrocarbons Capture for Natural Gas Upgrading by Tuning van der Waals Interactions in fcu-Type Zr-MOFs

Industrial & Engineering Chemistry Research ◽

10.1021/acs.iecr.7b03341 ◽

2017 ◽

Vol 56 (49) ◽

pp. 14633-14641 ◽

Cited By ~ 17

Author(s):

Guopeng Han ◽

Keke Wang ◽

Yaguang Peng ◽

Yuxi Zhang ◽

Hongliang Huang ◽

...

Keyword(s):

Natural Gas ◽

Van Der Waals ◽

Van Der Waals Interactions ◽

Higher Hydrocarbons

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Technique and results of experimental determination of the compressibility factor of the natural gas

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2021-9-35-40 ◽

2021 ◽

pp. 35-40

Author(s):

Denis Y. Kutovoy ◽

Igor A. Yatsenko ◽

Vladimir B. Yavkin ◽

Aydar N. Mukhametov ◽

Petr V. Lovtsov ◽

...

Keyword(s):

Natural Gas ◽

Equations Of State ◽

Compressibility Factor ◽

High Accuracy ◽

State Equations ◽

Actual Problem ◽

Temperature Range ◽

Relative Value ◽

Compressibility Coefficient

The actual problem of the possibility of using the equations of state for the gas phase of natural gas at temperatures below 250 K is considered. To solve it, the compressibility coefficients of natural gas obtained experimentally with high accuracy are required. The technique was developed and experimental study was carried out of compressibility factor aiming expanding temperature range of the state equations GERG-2004 and AGA8-DC92. The proposed technique is based on the fact that to assess the applicability of the equation of state, it is sufficient to obtain the relative value of the compressibility coefficient and not to determine its absolute value. The technique does not require complex equipment and provides high accuracy. The technique was tested on nitrogen, argon, air and methane. Uncertainty of determination of the compressibility factor is not greater than 0.1 %. For two different compositions of natural gas, obtained experimental data were demonstrated that the equations of state GERG-2004 and AGA8-92DC provide uncertainty of the calculation of the compressibility coefficient within 0.1 % in the temperature range from 220 K to 250 K and pressure below 5 MPa.

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