Achieving acceptable propane conversion in the endothermic propane dehydrogenation (PDH) reaction demands high temperatures, which exacerbate the activity-stability trade-off through low propylene selectivity and accelerated coking deactivation. Addressing this, we leverage the essence of Le Chatelier's principle-shifting reaction equilibrium through rapid in situ H2 removal-a strategy conventionally deemed unattainable on Al2O3 supports due to hydrogen spillover limitations. The synergistic sites between the La1-SnOx promoter and Pt enable the redistribution of surface H species away from the Pt active centers. Consequently, the La1-Ptn/SnOx/Al2O3 catalyst achieves propane conversions approaching the thermodynamic equilibrium conversion over 300-600 °C. Moreover, modulation of hydrogen surface diffusion behavior influences unselective C-C(H) scission of propylene and modifies coke structure and secondary cracking propensity, which is associated with the substantially improved durability observed for La1-Ptn/SnOx/Al2O3 compared to the Ptn/SnOx/Al2O3 (commercial mimic) catalyst. This superior performance demonstrates that, the introduction of La1-SnOx not only overcomes the inert hydrogen-trapping nature of Al2O3, but also alleviates the conventional activity-stability trade-off in PDH catalysis, illustrating how atomically dispersed promoters can circumvent intrinsic support limitations and thereby expand the performance boundaries of Al2O3-based dehydrogenation catalysts.
Wu et al. (2026) studied this question.