A process monitoring microreactor assembly for real-time reaction analysis using inline near-infrared spectroscopy and chemometrics

• DOI: 10.1007/s00216-025-05779-2
• Publication Date: 2025-02-07T02:54:58Z
• Authors: Lukas Mahler; Pascal Desel; Marcel Sladkov; Andreas Roppertz; Christian Mayer; Martin Jaeger
• Keywords: Microreactor; Chemometrics; Process Analytical Technology; Exothermic reaction

Abstract The occurrence of highly exothermic and potential runaway reactions represents a significant hazard to workers, facilities, the surrounding ecosystem. Due their high reaction velocity, these often prove difficult monitor. In many instances, recorded data result from several single-quantity sensors, such as temperature pressure sensors. Yet, deviations anticipated process, thus potentially hazardous parameters, may only be identified by combination sensor data, leaving cause unexplained. this study, custom-built microreactor in with in-line near-infrared spectroscopy off-line gas chromatography was employed allow monitoring acid-catalyzed esterification acetic acid methanol. Using spectrometer conjunction partial least squares regression models, reactant product concentrations could determined at various residence times temperatures. This approach enabled safe efficient investigation previously unexamined parameter ranges expansion design space experiments. spectra were subjected principal component analysis classification order obtain additional qualitative information. conversions space–time yields calculated obtained data. values indicated that delivered up twice those commonly used batch reactors. study hence demonstrates efficacy spectroscopic methods for microreactors application micro process analytical technologies. Graphical