Profiling the short-lived cationic species generated during catalytic dehydration of short-chain alcohols

Abstract

Short-chain alcohols are important products of biomass conversion and can be further converted into platform chemicals via catalytic dehydration. Although cationic species are believed to be intermediates in the alcohol-to-hydrocarbon processes, directly observing them is still a challenge due to the lack of efficient tools to deal with their instability and short lifetimes. Here we integrate a micro catalytic reactor onto the ion inlet of an Orbitrap mass spectrometer for high-speed, high-sensitivity, and high-throughput detection of the short-lived cationic species generated during dehydration of short-chain alcohols over heterogeneous catalysts. Hundreds of cationic species can be feasibly observed within the catalytic alcohol dehydration on acidic zeolites H-Beta and H-ZSM5. It is demonstrated that these cationic species may feasibly reveal the catalytic reaction activity and selectivity. This strategy has the potential to inform catalyst development and to help refine reaction conditions in the future.