Vapor-liquid equilibria for glycol ether + water systems

a b s t r a c tA generalized NRTL model was previously proposed for the modeling of non ideal systems and was extended to the prediction of phase equilibria under pressure according to the cubic NRTL-PR EoS. In this work, the model is reformulated with a predictive k ij temperature and composition dependent mixing rule and new interaction parameters are proposed between permanent gases, ethane and nitrogen with hydrocarbons, ethane with water and ethylene glycol. Results obtained for excess enthalpies, liquid-vapor and liquid-liquid equilibria are compared with those provided by the literature models, such as VTPR, PPR78, CPA and SRKm. A wide variety of mixtures formed by very asymmetric compounds, such as hydrocarbons, water and ethylene glycols are considered and special attention is paid to the evolution of k ij with respect to mole fractions and temperature.

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“…NRTL-PR fitted parameters: H2O (1)-benzene (2) [191] (CPA curves from Haghighi et al [195] with k ij = -0.2313 + 5.6294 × 10 −4 T).…”

Section: Tablementioning

confidence: 99%

A new formulation of the predictive NRTL-PR model in terms of kij mixing rules. Extension of the group contributions for the modeling of hydrocarbons in the presence of associating compounds

Escandell

Neau

Nicolas

2011

Fluid Phase Equilibria

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“…Solid line, CPA; dashed line, NRTL. Experimental data are from Gmehling et al,22 Chiavone et al,23 and Tsuji et al24 …”

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confidence: 99%

Cubic Plus Association Equation of State for Flow Assurance Projects

Santos

Abunahman

Tavares

et al. 2015

Ind. Eng. Chem. Res.

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Thermodynamic hydrate inhibitors such as methanol, ethanol, (mono) ethylene glycol (MEG), and triethylene glycol (TEG) are widely used in the oil and gas industry. On modeling these compounds, we show here how the CPA equation of state was implemented in an in-house process simulator as an in-built model. To validate the implementation, we show calculations for binary systems containing hydrate inhibitors and water or hydrocarbons using the Cubic Plus Association (CPA) and Soave−Redlich−Kwong (SRK) equation of states, also comparing against experimental data. For streams containing natural gas and water, CPA was applied to calculate the loss of the inhibitor to the vapor phase as a function of temperature and pressure. Simulations of dehydration units using TEG were conducted, and the CPA results were compared with that of two commercial simulators which used their available thermodynamic packages for glycol applications, proving that the CPA calculations are in good agreement with these models and showing that this is an adequate way to simulate complex mixtures containing natural gas, water, and hydrate inhibitors.

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“…In the MPA reaction and separation system, there existed three kinds of binary azeotropes, namely MP–H 2 O, MP–HAC and MPA–H 2 O mixtures, which increased the difficulties of the reactive distillation operation. Therefore a combination of extractive and reactive distillation was developed to separate the generated H 2 O from the system.…”

Section: Introductionmentioning

confidence: 99%

“…Moreover, the reactive distillation method could simultaneously achieve reaction and separation goals, which also reduced the investment and operating costs. [18][19][20][21][22][23][24][25] In the MPA reaction and separation system, there existed three kinds of binary azeotropes, namely MP-H 2 O, 26 MP-HAC 27 and MPA-H 2 O 4 mixtures, which increased the difficulties of the reactive distillation operation. Therefore a combination of extractive and reactive distillation was developed to separate the generated H 2 O from the system.…”

Section: Introductionmentioning

confidence: 99%

A combination of low‐temperature reactive and extractive distillation for methoxy‐2‐propyl acetate synthesis and separation process: simulations and experiments

Wang

Cai

et al. 2019

J of Chemical Tech & Biotech

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BACKGROUND Esterification of methoxy propanol (MP) and acetic acid (HAC) to methoxy‐2‐propyl acetate (MPA) is a typical reversible reaction. The yield of MPA is low owing to the limitation of chemical equilibrium. In the present study, with the goal of increasing the reaction conversion and preventing the NKC‐9 cation exchange resin catalyst from deactivation at high temperature, a process combining low‐temperature reactive and extractive distillation with cyclohexane (C6H12) as entrainer was investigated by process simulations and experiment methods. RESULTS The intrinsic kinetic parameters were obtained by catalyst activity evaluation in a batch reactor. Binary interaction parameters of thermodynamic models were determined by the measurement and fitting of vapor–liquid equilibrium data. The effects of different operating parameters on the reaction conversion and column performance were examined in detail, and a production process of MPA with an annual output of 56 000 tons was suggested. The results showed that the purity of MPA reached nearly 100% after further purification following reactive distillation, and the reaction temperature was controlled in the range 75–80 °C, which allowed long‐term operation thermal stability of the catalyst. CONCLUSION The developed low‐temperature reactive distillation method ensured a long life of the ion exchange resin catalyst, which should provide insights into further advances of MPA industrial production. © 2019 Society of Chemical Industry

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Vapor-liquid equilibria for glycol ether + water systems

Cited by 84 publications

References 8 publications

A new formulation of the predictive NRTL-PR model in terms of kij mixing rules. Extension of the group contributions for the modeling of hydrocarbons in the presence of associating compounds

A new formulation of the predictive NRTL-PR model in terms of kij mixing rules. Extension of the group contributions for the modeling of hydrocarbons in the presence of associating compounds

Cubic Plus Association Equation of State for Flow Assurance Projects

A combination of low‐temperature reactive and extractive distillation for methoxy‐2‐propyl acetate synthesis and separation process: simulations and experiments

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