Operando MAS NMR Reaction Studies at High Temperatures and Pressures
| Autor: | Eric D. Walter, Ali Chamas, Long Qi, David W. Hoyt, Jesse A. Sears, Hardeep S. Mehta, Susannah L. Scott |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Materials science
010405 organic chemistry 010402 general chemistry 01 natural sciences Chemical reaction Supercritical fluid 0104 chemical sciences Surfaces Coatings and Films Electronic Optical and Magnetic Materials Catalysis Solvent Chemical species General Energy Hydrogenolysis Phase (matter) Physical chemistry Physical and Theoretical Chemistry Bar (unit) |
| Zdroj: | The Journal of Physical Chemistry C. 122:8209-8215 |
| ISSN: | 1932-7455 1932-7447 |
| DOI: | 10.1021/acs.jpcc.7b11442 |
| Popis: | Operando MAS NMR studies provide unique insights into the details of chemical reactions; comprehensive information about temperature- and time-dependent changes in chemical species is accompanied by similarly rich information about changes in phase and chemical environment. Here we describe a new MAS NMR rotor (the WHiMS rotor) capable of achieving internal pressures up to 400 bar at 20 °C or 225 bar at 250 °C, a range that includes many reactions of interest. The MAS NMR spectroscopy enabled by these rotors is ideal for studying the behavior of mixed-phase systems, such as reactions involving solid catalysts and volatile liquids, with the potential to add gases at high pressure. The versatile operation of the new rotors is demonstrated by collecting operando 1H and 13C spectra during the hydrogenolysis of benzyl phenyl ether, catalyzed by Ni/γ-Al2O3 at ca. 250 °C, both with and without H2 (g) supplied to the rotor. The 2-propanol solvent, which exists in the supercritical phase under these reaction condi... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|