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In the present work, the liquid-liquid phase equilibrium data for the glycerol-methanol-methyl oleate and glycerol-monoolein-methyl oleate ternary systems were determined experimentally and compared with predictions of the UNIFAC and UNIFAC-Dortmund models. Liquid two-phase multicomponent systems consisting mainly of these chemical species are found in some industrially important transesterification reactions. For the glycerol-methanol-methyl oleate ternary system at 60°C, the predictions of UNIFAC and UNIFACDortmund are in good agreement with the experimental results. For the ternary glycerol-monoolein-methyl oleate system at 135°C, the predictions of UNIFAC and UNIFAC-Dortmund deviate significantly from the experimental data and are only qualitatively correct. The reliability of the experimental data was determined through Othmer-Tobias plots.

Optimization under uncertainty is considered necessary for robust process design and operation. In this work, a new approach is proposed to solve a kind of nonlinear optimization problem under uncertainty, in which some dependent variables are to be constrained with a predefined probability. Such problems are called optimization under chance constraints. By employment of the monotony of these variables to one of the uncertain variables, the output feasible region will be mapped to a region of the uncertain input variables. Thus, the probability of holding the output constraints can be simply achieved by integration of the probability density function of the multivariate uncertain variables. Collocation on finite elements is used for the numerical integration, through which sensitivities of the chance constraints can be computed as well. The proposed approach is applied to the optimization of two process engineering problems under various uncertainties.

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In order to design packed columns for multiphase operation it is necessary to include reliable data on the flow behavior in the model. Since experiments inside packings are very difficult to perform, CFD simulations are considered to be a sensible approach as numerical experiments. To obtain reliable results validation is inevitable. We present the validation of two-and three-phase film flow under transient conditions. This application is not abundant in literature. Numerical results are compared to data from own experiments. A statement is given on the usability of a VOF-like code for such applications.