• 공업화학
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• 제16권6호
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• pp.749-754
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• 2005

이성분 methanol/3-methyl-1-butanol계에 대하여 정온하 즉 50, 55 60, 65 및 $70^{\circ}C$에서의 기-액평형치를 측정하고, 그 측정치를 이용하여 기-액평형치를 추산하는 추산식을 이끌어 내었다. 측정치와 추산치를 비교 검토한 결과 기상조성의 몰분율은 ${\pm}0.0007$의 오차범위 내에서 잘 일치하고, methanol/3-methyl-1-butanol계에 대한 과잉 몰부피를 측정한 결과 전체 조성범위에서 양의 편차를 나타내며 최대치는 x= 0.683에서 $0.096cm^3/mol$로 나타났다.

• Korean Chemical Engineering Research
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• 제57권1호
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• pp.73-77
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• 2019

Isothermal (vapor + liquid) equilibrium data measurements were undertaken for the binary mixtures of (propylene oxide + 1-pentanol) system at three different temperatures (303.15, 318.15, and 333.15) K. The Peng-Robinson-Stryjek-Vera equation of state (PRSV EOS) was used to correlate the experimental data. The van der Waals one-fluid mixing rule was used for the vapor phase and the Wong-Sandler mixing rule, which incorporates the non-random two liquid (NRTL) model, the universal quasi-chemical (UNIQUAC) model and the Wilson model, was used for the liquid phase. The experimental data were in good agreement with the correlation results.

• Bulletin of the Korean Chemical Society
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• 제23권6호
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• pp.811-817
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• 2002

Gibbs ensemble Monte Carlo simulations were performed to calculate the vapor-liquid coexistence properties for the binary mixtures $CO_2/CH_3OH$, $CO_2/C_2H_5OH$, and $CO_2/CH_3CH_2CH_2OH.$ The configurational bias Monte Carlo method was used in the simulation of alcohol. Density of the mixture, composition of the mixture, the pressure-composition diagram, and the radial distribution function were calculated at vapor-liquid equilibrium. The composition and the density of both vapor and liquid from simulation agree considerably well with the experimental values over a wide range of pressures. The radial distribution functions in the liquid mixtures show that $CO_2$ molecules interact more stogly with methyl group than methylene group of $C_2H_5OH$ and $CH_3CH_2CH_2OH$ due to the steric effects of the alcohol molecules.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.245-249
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• 2003

Vapor-liquid equilibrium data were obtained for system of propane + R227ea (Heptafluoropropane) over the temperature range from 253.15 K to 323.15 K at 10 K intervals. Experiments were performed in a circulation type apparatus by injecting vapor through liquid pool using a magnetic pump. This system forms azeotrope in the temperature range of this study. The experimental results were correlated with the Peng-Robinson (PR) equation of state and Redlich-Kwong-Soave (RKS) equation of state using the van der Walls one-fluid mixing rule and were compared with each other.

• 설비공학논문집
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• 제12권11호
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• pp.1031-1037
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• 2000

Isothermal vapor-liquid equilibrium(VLE) data have been obtained for the systems of propane(R290)+1,1,1,2-tetrafluoroethane(R134a) and 1,1,1,2-tetrafluoroethane(R134a)+isobutane(R60A) in the temperature range of 253.15 to 323.15K. Experiments were performed in a circulation type apparatus by injecting vapor through liquid pool using a magnetic pump. Both systems form azeotropes in the temperature range of this study. The experimental results were estimated with the Peng-Robinson equation of state. When the temperature-dependent binary interaction parameter was used in the Peng-Robinson equation of state, the absolute average deviation of the measured bubble point pressures from the values correlated by the Peng-Robinson equation was 0.65% and 0.78% for R290+R134a and R134a+600a, respectively. Azeotropic compositions for both systems were presented.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.142-147
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• 2008

This paper reports an analysis of self-pressurization in a closed cryogenic liquid storage system and its comparison with experimental data using liquid nitrogen. Partial equilibrium model(PEM), revised thermodynamic analysis of homogeneous model, has been applied for the pressurization in a closed tank. The vapor and liquid bulk temperature and the liquid-vapor interface temperature are separately calculated as their own representative values in this analysis. The analysis results of the partial equilibrium model are compared with the experimental data and other preceding homogeneous temperature models for validation.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2001년도 제22회 KOSCI SYMPOSIUM 논문집
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• pp.106-118
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• 2001

A rigorous study of single droplet vaporization under quiescent high pressure atmosphere is attempted adopting method of flash evaporation calculation for vapor-liquid equilibrium. Results due to flash method shows excellent agreement with measurement. Also shown is the present model fairly capable of depicting transients of droplet vaporization under high pressure environment, such as ambient gas solubility, property variation, and multicomponent transports. Systematic treatment of these effects with emphasis on vapor-liquid phase equilibrium revealed; conventional treatment for subcritical droplet vaporization, such as $d^2$-law, leads to erroneous prediction of droplet history, augmented gas solubility is significant under supercritical pressure, and vaporization rate proportionally increase with pressure.

• 설비공학논문집
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• 제11권1호
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• pp.91-99
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• 1999

Vapor-liquid equilibrium apparatus is designed and set up. The equilibrium data of two binary systems, HFC-32/143a and HFC-143a/134a, are measured. Fifteen equilibrium data for HFC-32/143a and HFC-143a/134a systems are measured over the temperature range 263.15~283.15K at 10K interval and the composition range 0.10~0.80, respectively. And vapor-liquid equilibrium data are calculated using equation of state and correlation of activity coefficient and compared with the present data. Equation of state is used CSD and RKS equations and correlation of activity coefficient is used Margules' and Van Ness and Abbott's correlations. Real behavior of HFC-32/143a system has very large deviation with Raoult's rule which is ideal behavior. But real behavior of HFC-143a/134a system is similar to ideal behavior. The calculated data from CSD equation are compared with the data in the open literatures and the calculated data from REFPROP. In the results for REFPROP, the relative deviations of bubble point pressure for HFC-32/143a system are within -2.16~0.84% for CSD equation and within -0.20~1.10% for RKS equation. And the relative deviations of bubble point pressure for HFC-143a/134a system are within -0.45~0.12% and -0.20~2.8% for CSD and RKS equations, respectively.

• Korean Chemical Engineering Research
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• 제56권2호
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• pp.222-228
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• 2018

석유화학산업의 대표적인 물질로 쓰이는 벤젠은 각종 화학 제품의 기초 물질이다. 그러나 일반적으로 벤젠은 석유화학 산업에서 순수 물질로 존재하지 못하고 알코올류와 벤젠 혼합물로 존재하게 된다. 또한 알코올을 한 성분으로 하는 혼합물은 공비 혼합물이 생성되기 때문에 분리 정제를 위해서는 상평형 데이터가 필수적이다. 본 연구에서는 알코올을 대표하는 1-프로판올을 사용하여 1-프로판올/벤젠 계에 대하여 재순환 평형장치를 이용하여 평형 온도/압력 효과에 따른 상평형 연구를 수행하였다. 측정된 기-액 평형 데이터는 UNIQUAC 식과 WILSON 식을 이용하여 상관관계 시키고 Gibbs/Duhem식을이용하여열역학적건전성을확인하였다. 상평형실험결과 RMSE (Root Mean Square Error)와 AAD (Average Absolute Deviation)는 두 모델식에서 0.05 이하의 값을 보여 실험값과 계산 값이 잘 일치함을 알 수 있었다. 또한 Gibbs/Duhem식을 이용하여 열역학적 건전성을 판별한 결과 잔류항 값이 ${\pm}0.2$ 이내에 분포하는 것을 통해 데이터에 대한 건전성을 확인할 수 있었다.

• 공업화학
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• 제10권5호
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• pp.677-681
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• 1999

휘발성 액체 혼합물의 분리공정에 필요한 증류탑 설계의 필수 요건인 기-액평형에 관한 연구로서 cyclohexanol-cyclohexanone 2성분계에 대한 감압하 즉 150, 300 및 500 mmHg에서의 기-액평형치를 측정하고, 이 측정치와 30, 100, 200, 395 및 750 mmHg에서의 이미 발표된 기-액평형치를 이용하여 비휘발도와 익조성의 관계로부터 cyclohexanol-cyclohexanone 2성분계의 기-액평형치를 추산하는 추산식을 구하고, 여기서 구한 추산치를 실측치 및 문헌치와 비교 검토하였다. 그 결과 적은 오차 범위에서 잘 일치함을 확인하였다.