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The chemical and biotechnology industries are facing new challenges in the use of renewable resources. The complex nature of these materials requires the use of advanced techniques to understand the kinetics of reactions in this context. This study presents an interdisciplinary approach to analyze cofactor coupled enzymatic two-substrate kinetics and competitive two-substrate kinetics in a fast and efficient manner. By studying the adsorption energy distribution (AED), it is possible to determine the individual parameters of the reaction kinetics. In the case of a single alcohol reaction, the AED is able to identify parameters in agreement with the literature with few experimental data points compared to classical methods. In the case of a competitive reaction, AED analysis can automatically determine the number of competing substrates, whereas traditional nonlinear regression requires prior knowledge of this information for parameter identification. [ABSTRACT FROM AUTHOR]

Membrane processes are considered as comparably mild separation processes offering the potential for significant energy savings compared with azeotropic distillation processes. Despite higher investment and material costs, they are of particular interest for improving the energy efficiency in the chemical industry. However, energy savings of more than 20%–30% are rarely reported and even a general superiority can be disputed. To further elucidate this controversial, the current study pursues a quantitative assessment of the thermodynamic efficiency of pervaporation and vapor permeation processes with stand‐alone distillation and hybrid membrane‐assisted distillation processes for the separation of azeotropic mixtures. The results confirm the case‐dependent potential of distillation processes to outperform membrane‐assisted separations in terms of energy efficiency, considering proper heat integration. Although energy efficiency is becoming significantly important, it should be considered in the context of economic performance to determine an optimal trade‐off and to select the best process alternative during conceptual process design. [ABSTRACT FROM AUTHOR]

In the context of process intensification, milli-structured plate reactors provide significant advantages over conventional reactors in terms of heat and mass transfer as well as process safety. The ART® plate reactor PR37 of Ehrfeld Mikrotechnik GmbH offers excellent heat transfer, narrow residence time distributions and high mixing efficiency, while simultaneously allowing an effective scale-up to industrial applications due to its modular set up. This does not only enable the realization of novel process windows exceeding the limits of conventional reactors, but also provides optimal prerequisites for kinetic modelling due to the well-defined process conditions, providing key information regarding process design and optimization. The integration of the ART PR37 with Model-based Design of Experiments (MBDoE) allows for an intensification of kinetic studies, combining the well-defined operating conditions with a rapid and targeted identification of kinetic models. In the current study this combination is applied to successfully identify the kinetics of a multistep aromatic nucleophilic substitution reaction with low experimental effort, saving time and resources compared to conventional factorial Design of Experiments. [ABSTRACT FROM AUTHOR]

Distillation-based separation processes, such as extractive or heteroazeotropic distillation, present important processes for separating azeotropic mixtures in the chemical and biochemical industry. However, heteroazeotropic distillation has received much less attention than extractive distillation, which can be attributed to multiple reasons. The phase equilibrium calculations require a correct evaluation of phase stability, while the topology of the heterogeneous mixtures is generally more complex, comprising multiple azeotropes and distillation regions, resulting in an increased modeling complexity. Due to the integration of distillation columns and a decanter, even the simulation of these processes is considered more challenging, while an optimal process design should include the selection of a suitable solvent, considering the performance of the integrated hybrid process. Yet, the intricate mixture topologies largely impede the use of simplified criteria for solvent selection. To overcome these limitations and allow for a process-based screening of potential solvents, the current work presents a topology-based initialization and optimization approach for designing heteroazeotropic distillation processes. The systematic initialization enables an efficient evaluation of different solvents with different mixture topologies, which is further exploited for optimization-based sensitivity analysis and multi-objective optimization. Three case studies are analyzed with about 170 individually optimized process designs, including stage numbers, feed locations, phase ratios, and heat duties. [ABSTRACT FROM AUTHOR]

While rate‐based models are available in commercial flowsheet simulation tools, packed distillation columns are still mostly designed based on the equilibrium stage model in combination with HETP values. In order to discriminate between both types of models in a simple way, this article proposes an algorithmic test, based on a geometric criterion for total reflux operation. Substantial differences are illustrated especially for wide‐boiling mixtures, while component‐specific mass transfer rates either increase or reduce the deviation. The derived results are validated by dedicated experiments. [ABSTRACT FROM AUTHOR]

The growing demand for flexible and compact separation technologies has promoted the application of high‐gravity technology, like rotating packed beds (RPBs). Mass transfer characterization and packing design play an important role in the development of this technology. This article provides a systematic approach towards the evaluation of packing and the development of advanced packing design for distillation in RPBs. For the latter, an additive manufacturing approach is used to develop a new Zickzack packing for RPBs. The new packing provides better mass transfer at reduced pressure drop compared to available conventional packings, while being competitive in terms of mass transfer with the industrially applied rotating zigzag bed at significantly reduced pressure drop. [ABSTRACT FROM AUTHOR]

The capacity of today's gas‐liquid contacting equipment such as tray or packed columns is limited by the gravitational‐driven liquid flow. Intensified equipment applying centrifugal force offers great potential for enhancing the mass transfer and for reducing equipment size. Yet, detailed knowledge about the liquid flow inside rotating packings is scarce due to limited accessibility with conventional measurement systems. In this study, a gamma‐ray computed tomography is employed to quantify the liquid hold‐up and its distribution in the moving packing. [ABSTRACT FROM AUTHOR]