Nitrogen-doped Carbon-coated Al 2 O 3 supported Co 3 O 4 nanoparticles for Fischer-Tropsch synthesis: Boosting durability and Olefins selectivity

Alkali metal modification of cobalt-based Fischer-Tropsch synthesis catalysts suffers from poor stability and decreased activity. Exploring new strategies to enhance olefin selectivity and catalyst stability is of significant importance. In this work, a nitrogen-doped carbon layer-modified Co/NC-Al ₂ O ₃ catalyst was prepared using oleylamine as the nitrogen source and glucose as the carbon source. Under conditions of 230 ℃, 1 MPa, and 6 SL·g ^− 1 ·h ^− 1 , the Co/NC-Al ₂ O ₃ catalyst achieved an activity of 4.2×10 ^− 5 molCO·gCo ^− 1 s ^− 1 with an olefin selectivity of 34.4%, while exhibiting high stability. Characterization and performance results demonstrate that: the electron-donating effect of pyrrolic nitrogen enriches electrons in adjacent metallic Co, enhancing CO adsorption and activation while inhibiting secondary hydrogenation of α-olefins, thereby increasing olefin selectivity; The improved stability originates from the confinement effect of the carbon layer and the stabilizing role of graphitic nitrogen on Co nanoparticles.