This work presents and evaluates an approach to obtain and model kinetic data by combining a microreactor setup and real-time reaction monitoring through inline Fourier transform infrared spectroscopy with nonsteady-state conditions and self-modeling curve resolution (SMCR). Two model reactions, imine synthesis of benzaldehyde with benzylamine and deprotonation reaction with n-butyllithium, serve as a proof of concept and additionally demonstrate the method’s broad range of application, which includes simple reactions as well as complex mechanisms. Subsequent replications of the model reactions above (in terms of collection and modeling of kinetic data) using a more common approach (steady-state conditions and spectra evaluation using calibration curves) outline that the presented approach possesses greater time-efficiency compared to traditional methods (based on batch or steady-state studies), but that reliability of the resulting kinetic parameters should be reviewed carefully. However, when quick estimates are needed (analyzing the elementary reaction mechanism rather than developing a detailed scale-up model), research and industry alike may achieve significant time and cost savings through applying the outlined approach. To guide them in using this method in the most effective manner, this paper concludes by comparing two types of SMCR, soft- and hard-modeling, and argues for combining them.

Self-optimisation constitutes a very helpful tool for chemical process development, both in lab and in industrial applications. However, research on the application of model-free autonomous optimisation strategies (based on experimental investigation) for complex reactions of high industrial significance, which involve considerable intermediate and by-product formation, is still in an early stage. This article describes the development of an enhanced autonomous microfluidic reactor platform for organolithium and epoxide reactions that incorporates a successive combination of inline FT-IR spectrometer and online mass spectrometer. Experimental data is collected in real-time and used as feedback for the optimisation algorithms (modified Simplex algorithm and Design of Experiments) without time delay. An efficient approach to handle intricate optimisation problems is presented, where the inline FT-IR measurements are used to monitor the reaction’s main components, whereas the mass spectrometer’s high sensitivity permits insights into the formation of by-products. To demonstrate the platform’s flexibility, optimal reaction conditions of two organic syntheses are identified. Both pose several challenges, as complex reaction mechanisms are involved, leading to a large number of variable parameters, and a considerable amount of by-products is generated under non-ideal process conditions. Through multidimensional real-time optimisation, the platform supersedes labor- and cost-intensive work-up procedures, while diminishing waste generation, too. Thus, it renders production processes more efficient and contributes to their overall sustainability. Graphical abstract

In this work, a widely applicable routine to characterize the core, surface, stability, and optical properties of CdSe/CdS/ZnS core–shell–shell nanorods after multiple growth steps is established. First, size, shape, and shell thickness of the nanorods are characterized by transmission electron microscopy (TEM), analytical ultracentrifugation (AUC), and small angle X‐ray/neutron scattering (SAXS/SANS). In the next step, Fourier‐transform infrared (FT‐IR) spectroscopy, thermogravimetric analysis (TGA), and SANS measurements are applied to determine the surface species of nanorods. Then, the colloidal stability of the nanorods is investigated by UV–vis spectroscopy and dynamic light scattering (DLS) after different washing cycles. Finally, photoluminescence quantum yield (PLQY) of the nanorods during washing and sample storage is determined. With this highly complementary routine for particle characterization, the core, surface, stability, and optical properties of nanorods after multiple growth steps are resolved. The results demonstrate the importance of the developed toolbox to characterize such highly complex, anisotropic nanorods for a technical environment. This is of major importance for the handling of colloidal quantum materials and their quality control in industrial applications.

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