A sustainable supply chain: The controlled transformation of the biomass‐derived platform compounds levulinic acid (LA) and itaconic acid (IA) into the corresponding lactones, diols, or cyclic ethers (see picture) by using a multifunctional molecular catalyst is described.

An incremental approach for the identification of stoichiometries and kinetics of complex homogeneous reaction systems is presented in this paper. The identification problem is decomposed into a sequence of subproblems. First, the reaction fluxes for the various species are estimated on the basis of balance equations and concentration measurements stemming from isothermal experiments. This task represents an ill-posed inverse problem that requires appropriate regularization. Using target factor analysis, suitable reaction stoichiometries can then be identified. In a further step, the reaction rates are estimated without postulating a kinetic structure. Finally, the kinetic laws, i.e., the dependencies of the reaction rates on concentrations, are constructed by selecting the best model structure from a set of model candidates. This incremental approach is shown to be both efficient and flexible for utilizing the available process knowledge. The methodology is illustrated on the industrially relevant acetoacetylation of pyrrole with diketene. ᭧

We present an indirect hard modeling (IHM) approach for the quantitative analysis of reactive multicomponent mixtures with intermolecular interaction. It can be used when it is not possible to obtain calibration data in the composition region of interest. The goal of this work, specifically, is to analyze reactive systems, although the validation of the method is done with nonreactive systems. Compared to conventional hard modeling, the new approach reduces the manual work required for modeling and renders unnecessary the assignment of bands in mixture spectra to individual components. It is based on parametric models of the pure component spectra that are made just flexible enough to fit the spectra of the unknown mixtures, and it only requires small calibration data sets that may lie in different regions of the composition space. The application to infrared (IR) and Raman spectra of multicomponent systems is discussed.

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The effectiveness of an extractive distillation process relies on the choice of the extractive agent. In this contribution heuristic rules for entrainer selection and for the design of entrainers through computer-aided molecular design are reviewed first. The potential of the generated alternatives is then evaluated by their selectivity at infinite dilution and by the rectification body method (RBM). It is shown that a screening based on selectivity alone is not sufficient and could possibly lead to an unfavorable entrainer choice. The minimum entrainer flowrate and the minimum energy demand, calculated from the RBM, allow a more comprehensive evaluation of different entrainer alternatives. In a third step a rigorous MINLP optimization of the entire extractive flowsheet for the remaining entrainer candidates is executed to fix the remaining design degrees of freedom and to determine the best entrainer. Since a number of alternative entrainers have already been eliminated, only a few optimization runs are necessary. These steps form a framework which facilitates the systematic generation and evaluation of entrainer alternatives. The suggested synthesis framework is illustrated by a case study for the separation of acetone and methanol.