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

Harm Ridder; Christoph Sinn; Georg R Pesch; Jan Ilsemann; Wolfgang Dreher; Jorg Thöming

doi:10.1063/5.0044795

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

Rev Sci Instrum. 2021 Apr 1;92(4):043711. doi: 10.1063/5.0044795.

Authors

Harm Ridder¹, Christoph Sinn¹, Georg R Pesch¹, Jan Ilsemann², Wolfgang Dreher³, Jorg Thöming¹

Affiliations

¹ Chemical Process Engineering (CVT), Faculty of Production Engineering (FB 4), University of Bremen, Leobener Straße 6, 28359 Bremen, Germany.
² Faculty of Chemistry (FB 2), Institute of Applied Physical and Chemistry (IAPC), University of Bremen, Leobener Straße 6, 28359 Bremen, Germany.
³ In vivo MR Group, Faculty of Chemistry (FB 2), University of Bremen, Leobener Straße NW2, 28359 Bremen, Germany.

PMID: 34243384
DOI: 10.1063/5.0044795

Abstract

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 CO₂ 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.