Software-guided microscale flow calorimeter for efficient acquisition of thermokinetic data

Abstract

Fast chemical process development is inevitably linked to an optimized determination of thermokinetic data of chemical reactions. A miniaturized flow calorimeter enables increased sensitivity when examining small amounts of reactants in a short time compared to traditional batch equipment. Therefore, a methodology to determine optimal reaction conditions for calorimetric measurement experiments was developed and is presented in this contribution. Within the methodology, short-cut calculations are supplemented by computational fluid dynamics (CFD) simulations for a better representation of the hydrodynamics within the microreactor. This approach leads to the effective design of experiments. Unfavourable experimental conditions for kinetics experiments are determined in advance and therefore, need not to be considered during design of experiments. The methodology is tested for an instantaneous acid-base reaction. Good agreement of simulations was obtained with experimental data. Thus, the prediction of the hydrodynamics is enabled and the first steps towards a digital twin of the calorimeter are performed. The flow rates proposed by the methodology are tested for the determination of reaction enthalpy and showed that reasonable experimental settings resulted. Graphical abstract A methodology is suggested to evaluate optimal reaction conditions for efficientacquisition of kinetic data. The experimental design space is limited by thestepwise determination of important time scales based on specified input data.

Advances in Continuous Flow Calorimetry

“…In current research, computational fluid dynamics simulations were integrated into the calorimetry workflow. 54 The aim of further work is to develop an automated workflow from design of experiments to evaluation that is supported by modeling and simulations. Ładosz et al 36 also used a microreactor from Little Things Factory, although this one was designed in-house.…”

“…In addition, the temporal and spatial resolution of the heat flow profile enabled the determination of the mixing time scales of the respective reactors in parallel to the heat of reaction. In current research, computational fluid dynamics simulations were integrated into the calorimetry workflow . The aim of further work is to develop an automated workflow from design of experiments to evaluation that is supported by modeling and simulations.…”

Reactor performance estimation in microscale flow calorimeter for rapid characterization of exothermic reactions

“…A commercially available microreactor from Little Things Factory GmbH (Elsoff, Germany) is investigated in the simulations. The LTF-MS reactor from the MR-Lab series is studied in this work, which is the scale-up version of the LTF type-S reactor, which was employed in the microcalorimeter in previous works [14,15,27]. A schematic representation of reactor is shown in Fig.…”

Continuous milli-scale reaction calorimeter for direct scale-up of flow chemistry

“…Until today, only a few flow calorimeters have been described in literature and even fewer are commercially available [3]. Most of them are microreactor-like and work under almost isothermal conditions [3][4][5][6][7][8][9][10]. While micro-calorimeters are suitable to mimic microreactors, they are limited in describing flow chemistry at larger scale.…”