• Title/Summary/Keyword: Liquid-liquid equilibrium

Search Result 6, Processing Time 0.146 seconds

Correlation of Liquid-Liquid Equilibrium of Four Binary Hydrocarbon-Water Systems, Using an Improved Artificial Neural Network Model

  • Lv, Hui-Chao;Shen, Yan-Hong
    • Journal of the Korean Chemical Society
    • /
    • v.57 no.3
    • /
    • pp.370-376
    • /
    • 2013
  • A back propagation artificial neural network model with one hidden layer is established to correlate the liquid-liquid equilibrium data of hydrocarbon-water systems. The model has four inputs and two outputs. The network is systematically trained with 48 data points in the range of 283.15 to 405.37K. Statistical analyses show that the optimised neural network model can yield excellent agreement with experimental data(the average absolute deviations equal to 0.037% and 0.0012% for the correlated mole fractions of hydrocarbon in two coexisting liquid phases respectively). The comparison in terms of average absolute deviation between the correlated mole fractions for each binary system and literature results indicates that the artificial neural network model gives far better results. This study also shows that artificial neural network model could be developed for the phase equilibria for a family of hydrocarbon-water binaries.

Liquid-Liquid Equilibrium and Physical Properties of Aqueous Mixtures of Poly (Ethylene Glycol) 3000 with Tri-Potassium Citrate at Different pH: Experiment, Correlation and Thermodynamic Modeling

  • Ketabi, Mahnam;Pirdashti, Mohsen;Mobalegholeslam, Poorya
    • Journal of the Korean Chemical Society
    • /
    • v.63 no.1
    • /
    • pp.12-23
    • /
    • 2019
  • The new experimental data of liquid-liquid equilibrium (LLE) of aqueous two-phase system (ATPS) consisting of poly(ethylene glycol) 3000 + tri-potassium citrate at different pH were presented. It was found that an increase in pH resulted in the expansion of the two-phase region. The TLL and STL increased with increasing the pH values. The Merchuk equation can be appropriately employed to correlate the binodal curves and also the tie-line compositions were adjusted to both the Othmer-Tobias and Bancroft equations. In order to calculate the compositions of the phase and the ends of the tie-lines, density and refractive indices as two physical properties were used. Finally, the extended UNIQUAC, UNIFAC, Virial-(Mobalegholeslam & Bakhshi) and modified UNIQUAC-FV were used to measure the phase equilibria at different pH. The results of the models suggested that it can be used quite well to correlate the LLE in an aqueous solution of polymer-salt.

Liquid-Liquid Equilibrium for the Quaternary System Water + Tetrahydrofuran + Butyl Acetate + Isoamyl Alcohol Mixture at 298.15 K and Atmospheric Pressure (1 atm 298.15 K에서 4성분 Water+Tetrahydrofuran+Butyl Acetate+Isoamyl Alcohol 계의 액-액평형)

  • Kim, Young-Kyu;Ok, Dong-Seok;Park, Dong-Won
    • Korean Chemical Engineering Research
    • /
    • v.48 no.5
    • /
    • pp.632-637
    • /
    • 2010
  • Liquid-liquid equilibrium data for the quaternary system water +tetrahydrofuran + butyl acetate + isoamyl alcohol mixture were measured at 298.15 K and atmospheric pressure. Binodal curves, tie-lines, distribution, and selectivity for the quaternary system have been determined in order to investigate the effect of using binary solvents, butyl acetate and isoamyl alcohol, on extracting tetrahydrofuran from aqueous solution. In addition, these experimental tie-line data were also compared with the values predicted by the UNIFAC model. For the quaternary system, an average root-mean-square deviation for the system in 75/25, 50/50, and 25/75 mass ratios as mixed solvents are(3.35, 5.21 and 5.65) %, respectively.

Binary Vapor-Liquid Equilibria and Ternary Liquid-Liquid Equilibria for NMF Contained Systems (NMF를 포함하는 이성분계의 등온 기-액 평형과 삼성분계 액-액 평형)

  • Park, So-Jin;Han, Kyu-Jin;Won, Dong-Bok;Oh, Jong-Hyeok;Choi, Young-Yoon
    • Korean Chemical Engineering Research
    • /
    • v.43 no.2
    • /
    • pp.259-265
    • /
    • 2005
  • Binary isothermal vapor-liquid equilibrium(VLE) data were measured for water+n-methylformamide(NMF), benzene+NMF and toluene+NMF systems by using headspace gas chromatography(HSGC) at 353.15K. Additionally, the ternary liquid-liquid Equilibrium(LLE) data were determined by measuring of tie-line for the systems of NMF+benzene+n-heptane and NMF+toluene+n-heptane at 298.15 K. The measured isothermal binary VLE data have no azeotropes and were correlated well with $g^E$ model equations of Margules, van Laar, Wilson, NRTL and UNIQUAC. The experimental ternary tie line data were also correlated well with NRTL and UNIQUAC models. Besides their accuracy was analyzed by Hirata-Fujita and Maior-Swenson equations.

Study of Methane Storage through Structure Transition of Gas Hydrate (가스하이드레이트 구조 변형을 통한 메탄 저장에 관한 연구)

  • Lee, Ju-Dong;Lee, Man-Sig;Kim, Young-Seok
    • 한국신재생에너지학회:학술대회논문집
    • /
    • /
    • pp.54-57
    • /
    • 2006
  • Structure H formation experiments were conducted in a semi-batch stirred vessel using methane as the small guest substance and neohexane(NH), tert-butylmethylether(TBME) and methylcyclohexane(MCH) as the large molecule guest substance (LMGS). The results indicate that the rates of gas uptake and induction times are generally dependent on the magnitude of the driving force. When tert-butyl methyl ether is used as the LMGS rapid hydrate formation, much smaller induct ion time and rapid decomposition can be achieved. Liquid-liquid equilibrium (LLE) data for the above LMGS with water have been measured under atmospheric pressure at 275.5, 283.15K, and 298.15K. It was found that TBME is the most water soluble followed by NM and MCH. The solubility of water in the non-aqueous liquid was found to increase in the following order: MCH

  • PDF

A Study on the Recovery of Acetonitrile in the Process of Acrylonitrile (Acrylonitrile 제조공정에서 Acstonitrile의 회수에 관한 연구)

  • Lee, Jin-Woo;Park, Dong-Won
    • Applied Chemistry for Engineering
    • /
    • v.5 no.6
    • /
    • pp.1016-1023
    • /
    • 1994
  • In process of manufacturing acrylonitrile azeotrope of acetonitrile-water was come into being as by-product. For the purpose of recovering acetonitrile through solvent extraction process benzene, toluene, o-xylene, ethylacetate and monochlorobenzene as solvents were selected in order to separate acetonitrile from azeotrope of acetonitrile-water. In this study liquid-liquid equilibrium data were determined and consistency of the experimental data was investigated. The tie line and plait point for solvent(1)-water(2)-acetonitrile(3) system were determined at $25^{\circ}C$. The parameters in the NRTL, UNIQUAC and modified UNIQUAC model were predicted, distribution coefficient and selectivity of each solvent were determined respectively.

  • PDF