In this study, there was a need for VLE data for systems of oxygen-containing organic compounds. Experimental VLE data are presented for the following binary systems: a) 2-propanone (1) + 2-butanol (2) at 333.15K, 353.15K and 373.15K b) 2-propanone (1) + n-propanoic acid (2) at 333.15K, 353.15K and 373.15K c) 1-propanol (1) + n-butanoic acid (2) at 333.15K and 353.15K A test system (cyclohexane + ethanol at 323.15K) was measured to confirm the accuracy of the method and apparatus. With the exception of the test system, data for all the other binary systems investigated in this study are currently not available in the open literature. The dynamic recirculating stills of Joseph (2001) and Reddy (2006) were utilised to undertake the measurements. The experimental vapour pressure data measured in this study and the results obtained for the highly non-ideal test system were in excellent agreement with the literature data. It was thus concluded that the apparatus and operating procedures used were capable of producing highly accurate VLE data and confidence in the new data measured was obtained. Thermodynamic consistency testing was performed on the experimental VLE data using the point test (Van Ness et al., 1973), which provided an indication of the data’s quality and reliability. The data were thereafter subjected to data correlation to enable interpolation of the data and extrapolation to conditions other than those measured. Appropriate thermodynamic models (taking into account vapour-phase association in particular) were correlated to the data using the combined approach to VLE ( - method). For the calculation of the fugacity coefficients, three methods were used viz. the virial EOS and the Hayden-O’Connell correlation (1975); chemical theory and the Nothnagel et al. Formulation (1973); and the VPA/IK-CAPE EOS (Abbott and Van Ness, 1992). Three activity coefficients models were also used viz. the Wilson (1964) model; the NRTL model (Renon and Prausnitz, 1968); and the UNIQUAC model (Abrams and Prausnitz, 1975). In general, the models fitted the data well and the model parameters that were acquired are included. Theoretical developments involving associating components are ongoing. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2009.

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No description available.

The equilibrium properties of a spherical drop are investigated using the penetrable-sphere model of a fluid. To estimate the surface tension, a new statistical mechanical formula, the extension of the Triezenberg-Zwanzig result for a planar surface, is derived. The density profiles for use in this are obtained from an integral equation expressing the constancy of chemical potential through the interface. Numerical solutions can be obtained and from these numerical estimates for the surface tension. They are in good agreement with estimates from an independent thermodynamic route. These routes, as well as a further, zero-temperature, exact, analytic one, show that the surface tension of this model increases with decreasing drop size. The planar surface of the model is also briefly investigated using a well-known integrodifferential equation. Two approximations are made for the direct correlation function, one a systematic improvement on the other. They yield solutions for the density profile of a limited range of temperatures below the critical point. When the direct correlation function of a Lennard-Jones fluid is approximated the resulting equation for the profile resists numerical solution.

The major aim of this thesis has been to contribute to the understanding of the CH$ sb2$/OH/NH$ sb2$ group interactions by means of studies of alcohol-amine mixtures in the gas and liquid phases. / To study these interactions in the gas phase a Burnett type equipment was designed, built and operated at low pressure, obtaining experimental pressure-temperature (P-T) data for various systems including alcohol-amylamine mixtures. The P-T data were reduced by a method developed in this work to give values of second virial coefficients. Measurements on known systems were in excellent agreement with values reported in the literature. A group contribution method for predicting pure compounds and interaction second virial coefficients is presented. This method is equal, or superior to methods already available. / To study the CH$ sb2$/OH/NH$ sb2$ group interactions in the liquid phase, vapor-liquid-equilibrium (VLE) experiments with alcohol-amylamine mixtures were carried out in a Van Ness type apparatus. The raw data were reduced by a novel model free method using the second virial coefficients obtained previously for these mixtures. A group contribution method for predicting vapor-liquid-equilibria of multicomponent multigroup mixtures is proposed. Excellent predictions are obtained with this method. / Finally, computer experiments of Lennard-Jones fluid mixtures were carried out to help in the understanding of the local composition concept. This concept is of fundamental importance not only in the models used in this work but also in numerous other solution models.

Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 156-157). Also available via the Internet.

Thesis (M.S. in Chemical Engineering)--University of California, Berkeley, Sept. 1960. / Includes bibliographical references (leaf 56).

Thesis (Ph.D.)--McMaster University, 2003. / Advisor: R. L. Judd. Includes bibliographical references (leaves 253-256). Also available via World Wide Web.

Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Includes bibliographical references (p. 126-132).

CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / In the process of purification of biodiesel is of extreme importance washing methyl or ethyl ester rich- phase, since in conventional processes there is a great amount of water. During the washing is extracted primarily excess alcohol. Composition data for the washing process of biodiesel is still scarce in the literature and the study of liquid-liquid equilibrium provides the means to develop equipment and to optimize the extraction processes. Thus the main goal of this work is to determine equilibrium data for three different ternary systems: water - methanol - soybean biodiesel; corn biodiesel â methanol â water; methanol - coconut biodiesel - water at 20  C and 40  C. The experiments were carried out in equilibrium cells where the temperature was kept constant by thermostat control. The experimental determination was made by the method of densimetry. The consistency of data obtained for the tie lines was verified by correlations. It was verified by the ternary graphs, little influence of temperature on the systems studied. The equilibrium data were correlated liquid-liquid models for the activity coefficient NRTL, UNIQUAC and UNIFAC and proved quite satisfactory. / No processo de purificaÃÃo do biodiesel, a lavagem da fase rica em metil ou etil Ãster à de extrema importÃncia, visto que nos processos convencionais hà um grande gasto de Ãgua. Durante a lavagem à extraÃdo principalmente Ãlcool em excesso. Dados de composiÃÃes para a lavagem de biodiesel ainda sÃo escassos na literatura e o estudo do equilÃbrio lÃquido-lÃquido pode fornecer meios para o desenvolvimento de equipamentos e otimizaÃÃo dos processos de extraÃÃo. Dessa forma, o principal objetivo dessa dissertaÃÃo foi determinar dados de equilÃbrio lÃquido- lÃquido para os sistemas ternÃrios contendo biodiesel de soja + metanol + Ãgua, biodiesel de milho + metanol e Ãgua e biodiesel de coco + metanol + Ãgua, a 20 ÂC e 40 ÂC. Os experimentos foram feitos em cÃlulas de equilÃbrio mantendo a temperatura constante. A determinaÃÃo experimental das misturas ternÃrias foi feita pelos mÃtodos de titulaÃÃo e densimetria. A consistÃncia dos dados das linhas de amarraÃÃo foi verificada pelas correlaÃÃes de Othmer-Tobias e Hand. Verificou-se por meio de grÃficos ternÃrios, pouca influÃncia da temperatura sobre os sistemas estudados. Os dados de equilÃbrio lÃquido-lÃquido foram correlacionados pelos modelos para coeficiente de atividade NRTL, UNIQUAC e UNIFAC e mostraram-se bastante satisfatÃrios.