Dynamic In Situ NMR of Catalysis

University Of Southern California, Los Angeles CA

Investigators

Abstract

The project of Professor James Haw of the University of Southern California, supported by the Analytical and Surface Chemistry Program, seeks to achieve a fundamental understanding of the catalytic reactions that occur on zeolites and solid acid catalysts. A special pulse quench catalytic reactor has been designed that allows the investigation of catalytic reactions by nuclear magnetic resonance spectrometry. Changes in chemical intermediates can be followed with this device with a time resolution of 0.2 s; reactions are quenched by rapid cooling or by the introduction of inhibiting reagents. Theoretical calculations are also used to model the experimental NMR results via calculated NMR chemical shifts and quadrupolar coupling constants. Two specific examples of catalytic systems to be studied in this project include the synthesis of pyridine and butene isomerization, both are processes which are catalyzed by zeolites. Nuclear magnetic resonance spectrometry is used to study the catalytic transformation of simple adsorbed gases into more complex molecules on zeolites and solid acids. Professor James Haw at the University of Southern California has developed a combination of chemical reaction system with quenching that allows complex catalytic systems to be studied. The new analytical method will be used to study the industrially important projects of pyridine synthesis and the isomerization of butene, a precursor to synthetic rubber.