Impact of Heteroatom Speciation on the Activity and Stability of Carbon-Based Catalysts for Propane Dehydrogenation

Metal-free carbon catalysts represent attractive alternatives to platinum and chromium-containing systems for the on-purpose production of propylene, a crucial chemical building block, via non-oxidative propane dehydrogenation. However, the role of heteroatoms in determining reactivity and stability is poorly understood. Here, the study of a platform of polyaniline-derived and activated carbons, with distinct porous properties, and heteroatom type, content, and speciation, enables establishing improved structure-performance relationships. In-depth characterization reveals that, while several oxygen species potentially catalyze the reaction, carbonyl groups are the main functionality governing the activity. Oxygen loss via propane-driven water evolution is the main deactivation path. Six-fold enhanced stability evidenced over carbon catalysts derived from KOH-post-treated polyanilines demonstrates the importance of controlling the nanostructure for enhancing longevity.

Automated summary

The study focuses on different porous properties, heteroatom types, contents, and specifications in polyaniline-derived and activated carbon platforms. The main functionality governing activity is carbonyl groups, and the main deactivation path is oxygen loss via propane-driven water evolution. Carbon catalysts derived from KOH-post-treated polyanilines show significantly enhanced stability compared to others, highlighting the importance of controlling nanostructure for longevity.