The primary focus of this study is the measurement and modeling of binary and ternary VLE data. The measurements of binary and ternary systems were undertaken on a fully automated dynamic VLE apparatus. The glass dynamic VLE still was modified to handle pressures ranging from 0 to 500 kPa, however, the safest maximum pressure to which tests had been conducted was 350 kPa. Thus, this limit was not to be exceeded during the measurement of experimental data. The systems under investigation included the binary and ternary combinations of the following chemicals: n-hexane, 1-hexene and n-methyl-2-pyrrolidone (NMP) at isothermal conditions. A test system consisting of ethanol + cyclohexane was measured at 40 kPa, as well as the system of 1-hexene + NMP at 363.15 K and n-hexane + NMP at 363.15 K. Published literature data for these test systems were employed to verify the measured data for the test systems complied with thermodynamic consistency. All other data constitutes new data, currently unavailable in literature. The following isotherms were measured: 1) 1-hexene (1) + NMP (2) at 323.15, 343.15, 353.15 and 363.15 K 2) n-hexane (1) + NMP (2) at 353.15, 363.15, 378.15 and 383.15 K 3) 1-hexene (1) + n-hexane (2) at 343.15, 363.15 and 373.15 K, and 4) 1-hexene (1) +n-hexane (2) + NMP (2) at 363.15 K All system measurements were carried out on the glass low-to-medium pressure VLE still of Lilwanth (2011), with the exception of the test system ethanol + cyclohexane, which was carried out on the low pressure VLE glass still of Hirawan (2007). The two VLE stills, utilized to carry out measurements in this work, can operate isobarically and isothermally. The temperature on the stills of Hirawan (2007) and Lilwanth (2011) were controlled to within ±0.425 and ±0.089 K respectively and the accuracy of pressure control is to within ±0.320 and ±0.440 kPa respectively. In addition, for the calibration of the various systems: ethanol + cyclohexane, 1-hexene + NMP, n-hexane + NMP, 1-hexene + n-hexane and 1-hexene + n-hexane + NMP, the accuracies are: ±0.002, ±0.0034, ±0.0033, ±0.0066 and ±0.0083 of a mole fraction respectively. The binary interaction parameters obtained from modeling the three binary systems were used to predict the ternary system data. Thereafter, the experimentally measured data for the ternary system was then compared to the model prediction, which was completed on Dortmund Data Bank (DDB, 2011). The measured binary data was regressed utilizing the combined and the direct methods. For the direct method, the cubic equations of state (CEoS) used to describe the vapour phase included the Peng-Robinson (1976) and Soave-Redlich-Kwong (1972) equations combined with the mixing rule of Wong and Sandler (1992) in conjunction with the Gibbs excess energy models, namely the NRTL (1968) and UNIQUAC (1975) models, to describe the liquid phase non-idealities. For the combined method, the Gibbs excess energy activity coefficient models mentioned above were employed to represent the liquid phase imperfections and the vapour phase nonidealities were represented by cubic equations of state, as mentioned above, as well as the Hayden and O‟Connell (1975) virial equation of state for the calculation of the virial coefficients. To verify whether the measured data is thermodynamically consistent the point and direct tests were applied. Even though the direct test is a more stringent approach to testing thermodynamic consistency, for the systems 1-hexene + NMP and n-hexane + NMP, the point test was utilized as the primary means by which to quantify the data, as the associative effects of the NMP molecule effect the results obtained. For the system 1-hexene + n-hexane the direct test was used as the primary means to test the consistency of data, as no cross- or self-association is present. After extensive modeling was carried out, it was found that for the systems 1-hexene + NMP and n-hexane + NMP the model which enabled the best fit of the experimental data are the NRTL activity coefficient model in conjunction with the Hayden and O‟Connell virial equation of state (EoS). For the system 1-hexene + n-hexane the overall best fit model is the Peng-Robinson EoS in conjunction with the Wong-Sandler mixing rule and the NRTL activity coefficient model. A single set of binary interaction parameters for each of the three binary systems was obtained (via regression on Aspen Plus®) using the NRTL-HOC models. However, since Aspen Plus® cannot predict ternary system behaviour using the binary interaction parameters of the constituent systems, DDB was utilized. Further, DDB did not have available the HOC virial EoS (for enabling predictions), thus, it was decided to use the ideal gas model for representation of the vapour phase in conjunction with the NRTL activity coefficient model. The use of the ideal gas model does not compromise the integrity of the prediction in any way since the ternary system measurements were carried out in the dilute NMP region. Thus, since the main components in the ternary mixture at any one instant were 1-hexene and nhexane, and these components behave ideally, the ideal gas model is applicable. After the predicted behaviour for the ternary system was compared to the experimental data for the same system, the maximum percentage error encountered between the two data sets is 5%. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2012

Dissertation research involves development of Mobile Order Theory thermodynamic models to mathematically describe and predict the solubility, spectral properties, protonation equilibrium constants and two-phase partitioning behavior of solutes dissolved in binary solvent mixtures of analytical importance. Information gained provide a better understanding of solute-solvent and solvent-solvent interactions at the molecular level, which will facilitate the development of better chemical separation methods based upon both gas-liquid and high-performance liquid chromatography, and better analysis methods based upon complexiometric and spectroscopic methods. Dissertation research emphasizes chemical equilibria in systems containing alcohol cosolvents with the understanding that knowledge gained will be transferable to more environmentally friendly aqueous-organic solvent mixtures.

Fez-se um estudo monográfico das características gerais dos pseudo-haletos - pseudo-halogênios por estarem ligados aos estudos experimentais relatados na presente tese. Estudaram-se novos procedimentos para determinação de constantes de equilíbrio (baseados na linearização de curvas) e para obtenção de αo em regiões experimentalmente inacessíveis do ligante. Esses procedimentos foram exaustivamente testados em sistemas modelos antes de serem aplicados à solução de sistemas reais, com base experimental. O sistema Cu(II)/Br- foi estudado espectrofotometricamente, com tratamento iterativo dos dados experimentais, chegando-se às seguintes constantes de formação e absortividades molares dos três complexos: (Ver no arquivo em PDF). Relações lineares forum observadas para -ε vs. -n. Nova sistemática de medidas precisas de E1/2 da segunda onda de cobre(II) em azoteto e brometo (separação pouco definida das duas etapas), permitiu estudar com maior exatidão os complexos formados relativos a esses sistemas: (Ver no arquivo em PDF). Diagramas de potenciais envolvendo os sistemas Cu(II)/Cuo, Cu(I)/Cuo e Cu(II)/Cu(I), em meio de brometo e azoteto, permitiram tirar conclusões interessantes, especialmente, sobre o comportamento potenciométrico do eletrodo de membrana de CuS e Ag2S em presença de ânions N-3; e Br-. Observações preliminares foram feitas sobre o aparecimento de ondas catalíticas envolvendo peróxido de hidrogênio e o amálgama de cobre, formado na superfície do eletrodo gotejante. As experiências evidenciaram que o ciclo catalítico envolve a oxidação do amálgama a cobre(I) e cobre(II). Consideráveis diferenças de comportamento foram observadas entre os eletró1itos suportes de azoteto e acetato. No estudo polarográfico do sistema Cu(II)/Cu(Hg) em acetato, chegou-se a um processo conveniente de obtenção do E1/2 reversível por extrapolação à densidade de corrente zero. / A mono graphic study of the pseudohalide or pseudohalogen characteristics was done in order to better understand some experimental studies performed. New processes of determination of equilibrium constants were considered for treatment of experimental data. They consist in linearization of curves and achievement of experimental data of αo vs. ΙLΙ experimentally unaccessible regions of the ligand. The procedures were exaustively checked in model systems before its aplication to real systems. The copper(II)/bromide system was studied by spectrophotometry by an iterative treatment of experimental data of average molar absortivities. The formation constants and molar absortivities of the three detected complexes are: (See in the PDF file) Linear relationships were observed between the average molar absortivities and average ligand number. The polarographic study confirmed the stepwise reduction of copper(II) in bromide suporting electrolite. The following formation constants of the copper(I)-bromide complexes were obtained: (See in the PDF file). A new procedure for precise E1/2 measurements in the two copper waves in azide and bromide medium was applied at conditions where low definition between the two waves occurs. This permits to find more reliable equilibrium constants for the copper(I)/azide system: (See in the PDF file). Potential diagrams refered to the Cu(II)/Cuo, Cu(I)/Cuo and Cu(II)/Cu(I) systems in bromide and azide medium led to interesting conclusion, specially refered to the potentiometric behavior of a membrane selective electrode of CuS and Ag2S, in the presence of bromide and azide anions. Preliminary results were taken the existence of catalytic waves involving hidrogen peroxide and the copper amalgam formed at the dropping mercury electrode. The catalytic cicle is achieved through the oxidation of the amalgan to copper(I) and copper(II) by the peroxide in alkaline medium. Considerable differences were observed between the azide and acetate supporting electrolite.

Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Bibliography: leaves 254-255. / by Chau-Chyun Chen. / Sc.D.

Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1981. / MICROFICHE COPY AVAILABLE IN SCIENCE AND ARCHIVES. Science copy in 2 v. / Vita. / Bibliography: leaves 320-331. / by Ronald Ted Kurnik. / Sc.D.

Photocopy of typescript. / Digitized by Kansas Correctional Industries

[by] Laszlo Tisza, Paul M. Quay. / Repr. from Annals of physics. v. 25, no. 1. Oct. 1963.

Thesis (Ph.D.)--University of Tulsa, 1971. / Bibliography: leaves 34-36.

Thesis (M.Sc. (Physical Chemistry))--Mahidol University, 1978.

Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves 151-159). Also available on the Internet.