Promotion role of B doping in N, B co-doped humic acids-based porous carbon for enhancing catalytic performance of oxidative dehydrogenation of propane using CO2.

Thermal stability of carbon based materials is crucial to their catalytic performance in oxidative dehydrogenation at high temperature. This work aims at exploring the mechanism for B doping to improve thermal stability and catalytic performance of N, B co-doped carbon (HC-N-B) for oxidative dehydrogenation of propane using CO₂, which was prepared by using humic acids (HAs) extracted from Sheng Li lignite. Porous carbon (HC) from humic acids has low thermal stability in CO₂ and N-doping resulted in the decreased thermal stability of HC. Interestingly, B doping HC-N showed very high thermal stability in CO₂ (almost no weight-loss). Thus, HC-N-B could be used as considerable stable carbon catalysts with high catalytic activity for oxidative dehydrogenation of propane using CO₂. Compared to porous carbon (HC) and N-doping porous carbon (HC-N) from HAs, the HC-N-B could remain the high catalytic dehydrogenation activity in 5 h. It was found that B doping on the defect structure in carbon skeleton structure of the HC-N could greatly increase the thermal stability of surface defects of N-doped porous carbon in CO₂, and molecular simulation calculation results further confirmed that the existence of C-N-B and BC₃ structure in the carbon skeleton defects could act as catalytic active sites in dehydrogenation reaction, which could slightly enhance the catalytic activity of the HC-N-B and largely improved its catalytic stability of the HC-N-B. [ABSTRACT FROM AUTHOR]