In this paper, the authors recall and systemize the restrictions to the application of Job's method, illustrate its use associated to proton magnetic resonance spectral intensities, and present some results of a computer program they developed for the case of multiple equilibria.

While the design of products and processes involving ionic liquids (ILs) requires knowledge of the thermophysical properties for these compounds, the massive number of possible distinct ILs precludes their detailed experimental characterization. To overcome this limitation, chemists and engineers must rely on predictive models that are able to generate reliable values for these properties, from the knowledge of the structure of the IL. A large body of literature was developed in the last decade for this purpose, aiming at developing predictive models for thermophysical and transport properties of ILs. A critical review of those models is reported here. The modelling approaches are discussed and suggestions relative to the current best methodologies for the prediction of each property are presented. Since most of the these works date from the last 5 years, this field can still be considered to be in its infancy. Consequently, this work also aims at highlighting major gaps in both existing data and modelling approaches, identifying unbeaten tracks and promising paths for further development in this area.

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Effects of hard constraints in the stability of model-predictive control (MPC

This paper focuses on the fluid catalytic cracking (FCC) process and reviews recent developments in its modeling, monitoring, control, and optimization. This challenging process exhibits complex behavior, requiring detailed models to express the nonlinear effects and extensive interactions between input and control variables that are observed in industrial practice. The FCC models currently available differ enormously in terms of their scope, level of detail, modeling hypothesis, and solution approaches used. Nevertheless, significant benefits from their effective use in various routine tasks are starting to be widely recognized by the industry. To help improve the existing modeling approaches, this review describes and compares the different mathematical frameworks that have been applied in the modeling, simulation, control, and optimization of this key downstream unit. Given the effects that perturbations in the feedstock quality and other unit disturbances might have, especially when associated with frequent changes in market demand, this paper also demonstrates the importance of understanding the nonlinear behavior of the FCC process. The incentives associated with the use of advanced model-based supervision strategies, such as nonlinear model predictive control and real-time optimization techniques, are also presented and discussed.

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Over the last decade ionic liquids appeared as potential entrainers for extractive distillation processes. However experimental vapor-liquid equilibrium data for ionic liquid containing systems is still scarce since most conventional equilibrium cells are not adequate for these systems. To overcome that limitation a new isobaric microebulliometer, operating at pressures ranging from 0.05 to 0.1 MPa and requiring a sample volume lower than 8 mL was developed and validated in this work. The new apparatus was used to determine isobaric VLE data at pressures of 0.05, 0.07 and 0.1 MPa for eight binary mixtures of 1-ethyl-3-methylimidazolium chloride ([C 2 mim][Cl]), 1-butyl-3methylimidazolium chloride ([C 4 mim][Cl]), 1-hexyl-3-methylimidazolium chloride ([C 6 mim][Cl]), and choline chloride ([N 111(2OH) ][Cl]) with water and ethanol. The experimental data here measured were correlated with the NRTL model.

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