A large fixed bed reactor for MRI operando experiments at elevated temperature and pressure.

Rev Sci Instrum

Chemical Process Engineering (CVT), Faculty of Production Engineering (FB 4), University of Bremen, Leobener Straße 6, 28359 Bremen, Germany.

Published: April 2021

Recently, in situ studies using nuclear magnetic resonance (NMR) have shown the possibility to monitor local transport phenomena of gas-phase reactions inside opaque structures. Their application to heterogeneously catalyzed reactions remains challenging due to inherent temperature and pressure constraints. In this work, an NMR-compatible reactor was designed, manufactured, and tested, which can endure high temperatures and increased pressure. In temperature and pressure tests, the reactor withstood pressures up to 28 bars at room temperature and temperatures over 400 °C and exhibited only little magnetic shielding. Its applicability was demonstrated by performing the CO methanation reaction, which was measured operando for the first time by using a 3D magnetic resonance spectroscopic imaging sequence. The reactor design is described in detail, allowing its easy adaptation for different chemical reactions and other NMR measurements under challenging conditions.

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http://dx.doi.org/10.1063/5.0044795DOI Listing

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